A skateboarder with a mass of 67.0 kilograms (including the skateboard) rolls down from the top of a ramp, reaching a velocity of 7.30 meters per second at the bottom of the ramp. Assuming friction is 0, what was the potential energy of the skateboarder at the top of the ramp?

1,785 J.

59.70 J.

74.30 J.

489.1 J.

A Skateboarder With A Mass Of 67.0 Kilograms (including The Skateboard) Rolls Down From The Top Of A

Answers

Answer 1

The potential energy of the skateboarder at the top of the ramp is

489.1 J.

Is kinetic energy always equal to potential energy?

The amount of kinetic energy change and the amount of potential energy change are equal in all physical processes that take place in closed systems. When the kinetic energy rises, the potential energy falls, and vice versa.

Potential energy is the stored energy in any object or system as a result of its position or component arrangement. However, external factors like air or height have no effect on it. The energy of a moving object or system is referred to as kinetic energy.

Potential energy = kinetic energy

Potential energy = 1/2mv²

Potential energy = 1/2 × 67×7.3

Potential energy = 489.1 J.

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Related Questions

In 1979, Dr. Hans Liebold of Germany drove a race car 12.6 km with an average speed of 404 km/h. Suppose Liebold applied the brakes to reduce his speed. What was the car’s final speed if −3.00 MJ of work was done by the brakes? Assume the combined mass of the car and driver to be 1.00 × 103 kg

Answers

The vehicle's last speed if −3.00 MJ of work was finished by the brakes will be 398.45 km each hour.

What is the conservation of energy?

According to the principle of conservation of mass, energy cannot be gained or lost; it can only be converted from one form of energy to another. This indicates that only if energy is introduced from outside, a unit always uses the same quantity of energy.

In 1979, Dr. Hans Liebold of Germany drove a race vehicle 12.6 km with a typical speed of 404 km/h. Assume Liebold applied the brakes to decrease his speed. Expect the consolidated mass of the vehicle and driver to be 1.00 and 103 kg.

The final speed is given as,

1/2 x m [(v₂)² - (v₁)²] = 3 x 10⁶

1/2 x (1 + 103) x [(v₂)² - (404 x 18/5)²] = 3 x 10⁶

(v₂)² = 2057687.06

v₂ = 1,434.43 m/s

v₂ = 398.45 km per hour

The vehicle's last speed if −3.00 MJ of work was finished by the brakes will be 398.45 km each hour.

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A proton moves at 4.20 x 105 m/s in the horizontal direction. It enters a uniform vertical electric field with a magnitude of 7.60 * 103 N/C. Ignore any gravitational effects_ Find the time interval required for the proton to travel 4.50 cm horizontally. ns (b) Find its vertical displacement during the time interval in which it travels 4.50 cm horizontally. (Indicate direction with the sign of your answer.) mm (c) Find the horizontal and vertical components of its velocity after it has traveled 4.50 cm horizontally_ j km/s

Answers

The time interval required for the proton to travel 4.50 cm horizontally is  1.07 x 10⁻⁷ s , vertical displacement during the time interval in which it travels 4.50 cm horizontallyis  0.0043 m, and the horizontal and vertical components of its velocity after it has traveled 4.50 cm horizontally_ j km/s.

a. Let t be the amount of time needed for a proton to move 4.50 cm 0.045 m horizontally. It is calculable as follows:

t = d/v

where t is time, d is distance and v is velocity

t= d/v

t = 0.045m / 4.20 x 10⁵ m/s = 1.07 x 10⁻⁷ s

b. because the initial speed in the vertical direction is 0. So,

Thus, q E = ma.

ay= (Ey q)/m

Displacement is given by :

y=ut + 1/2ayt²

y =1/2 ((Ey q)/m) t²

y =(1/2)(7.60 x 10³ N/C x 1.67 x 10⁻¹⁹)(1.07 x 10⁻⁷)²

                     

y= 0.0043 m

c.Use the following kinematics equation for the vertical component of velocity:

V(y)²-u²= 2ayd

[tex]v_y=\sqrt{\frac{E_{y}q}{m}d_{y} } \\v_y=\sqrt{\frac{7.60 X 10^3 N/C _{} X 1.67 x 10^{-19}}{ 1.67 x 10^{-27}} 0.045[/tex]

v=1.8493 X10⁵ m/s

velocity horizontal component,

vₓ =d/t

vₓ= 0.045/( 1.07 x 10⁻⁷ s) = 4.20 x10⁵

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Compare the wavelength of an electron traveling at a speed of 1.0* 10^7m/s with that for a ball of mass 0.10kg traveling at 35m/s

Answers

The wavelength of the electron, given that it is travelling at 1.0×10⁷ m/s is higher than that of the ball travelleing at 35 m/s

How do I compare the wavelength of the electron and ball?

To compare the wavelength of both the electron and ball, we shall determin the the wavelength of both the electron and ball. Details below:

For electron:

Mass of electron (m) = 9.1×10⁻³¹ KgVelocity of electron (v) = 1.0×10⁷ m/sPlanck's constant (h) = 6.626×10⁻³⁴ JsWavelength of electron (λ) = ?

λ = 2h / mv

λ = (2 × 6.626×10⁻³⁴) / (9.1×10⁻³¹ × 1.0×10⁷)

λ = 1.46×10⁻¹⁰ m

For ball:

Mass of ball (m) = 0.10 KgVelocity of ball (v) = 35 m/sPlanck's constant (h) = 6.626×10⁻³⁴ JsWavelength of ball (λ) = ?

λ = 2h / mv

λ = (2 × 6.626×10⁻³⁴) / (0.10 × 35)

λ = 3.79×10⁻³⁴ m

From the above calculation we obtained:

Wavelength of electron = 1.46×10⁻¹⁰ mWavelength of ball = 3.79×10⁻³⁴ m

Thus, we can conclude that the the wavelength of the electron is higher than that of the ball.

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A crane lifts a crate upwards through a height of 20m. The lifted force provided by the crane is 5kN, how much work is done by the force? how much energy is transferred to the crate

Answers

The work done by the crane in lifting the crate is calculated to be 100 KJ.

How to calculate the work done when an object is on a height?

Energy is transferred as a gain in the object's gravitational potential energy when work is done to increase the height of the item. Potential energy refers to the work that an object does as a result of its height. An object with mass m at a height h has a gravitational potential energy PE, which is given by the relationship:

PE = m × g × h

where,

m = mass of the object

g = gravitational force acting upon the object

h = height of the object at which it is lifted

Now, it is given that,

Force provided by the crane = mg = 5 KN = 5000 N           (∵ 1kN = 1000N)

Height = 20 m

On substituting the given values in the above relation, we get:

PE = 5000N × 20m

PE = 100000 Joules or 100 kilo Joules

Hence, the work done by the crane in lifting a crate upwards is found to be 100 KJ in the form of potential energy.

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Height h = 20 m and force F = 5 kN are provided.

To Discover: Work Done, W

Work Done, as we are all aware, is the result of force and displacement. Here, we must compute the work performed by the crane in opposition to gravity.

Where,

W = mgh

The mass is m.

Gravitational acceleration, or g,

h is the height the item has gained.

mg = 5 kN for force.

1 kN = 1000 N

As a result, 5 kN equals 5*1000 N.

Replace with the value we obtain

→ W = 5000 × 20

→ W = 100000 J

→ W = 100000/1000 Kj

→ W = 100Kj

As a result, the crane's labour to raise the cargo was 100 KiloJoules.

According to work energy theorem Word Done = Energy Used

Thus, 100KJ is the required amount of Kinetic Energy required by the Crane.

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When you paddle a boat in the water, the force of your paddle
will push the water which will apply an equal force back on
you. True or false

Answers

The paddle will experience a force from the water equal to the product of the water pressure and the paddle's surface area.

what is pressure ?

Pressure (symbol: p or P) is the force applied perpendicular to the surface of an object per unit area across which that force is distribute  Gauge pressure (sometimes called gauge pressure)[a] is the pressure relative to the ambient pressure.

Various units are used to express pressure. Some of these are derived from dividing a unit of force by a unit of area; for example, the SI unit of pressure, the pascal (Pa), is one newton per square metre (N/m2); similarly, the pound-force per square inch (psi) is the conventional unit of pressure in the imperial and US customary systems. Pressure can also be stated in terms of normal atmospheric pressure; this pressure equals the atmosphere (atm).

The paddle will experience a force from the water equal to the product of the water pressure and the paddle's surface area. Any more power will only go to raise the speed of the paddle. Because of this, more water may be forced into a smaller space.

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Answer: The answer is ture

Explanation: Newtons third law which says

Imagine you work as a consultant, and your daily job involves listening to the constructive criticism of others. As part of your job, you must listen to opposing viewpoints to make important decisions. In this activity, you are a consulting dam engineer. You must make a decision about four different dams; should they be repaired, taken down, or left alone? You will listen to contrasting opinions about what should be done with the dams before you make the final decision. As the consulting dam engineer, what do you decide to do with this dam? Explain your reasoning. By making your decision, did you support the opinions of the mayor and/or the dam safety official? Why or why not? (Site 1)

Answers

The primary cause of the decision-making and construction process delays is a lack of knowledge. Never criticize a teammate in front of other teammates or the manager when giving them constructive criticism.

What to do as a consulting dam engineer and how to decide?

A great deal is that more information is required to portray the current structure, its background, and its make-up. They can go get another dam consulting engineer if it is too much trouble for them or if they don't like it.

However, there are a few things that are quite challenging to adhere to:

Observing how other people differ in their perspectives.observing how other people differ in their perspectives. Any of this dam's structural, meteorological, or environmental features should be taken into consideration.Taking the dam safety officer's advice into account

The absence of information in the query is what makes all of these challenges difficult. Thus, it is clear that the main cause of the decision-making and construction process delays is a lack of knowledge.

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Janelle pushes a box filled with books across the floor of her room. She then add some books to the box and pushes it with the same force across the same floor. How will the motion of the box change?

A . It will move slower because as mass increases, the force of friction between the surface also increases.

B. It will move faster because as mass increases, the force of friction between the surfaces decreases.

C it will move with the same speed because the mass of the object does not affect the force of friction between the surfaces.

D. It will move with the same speed because the same force was applied on the box in both of the cases

Answers

The motion of the box changes as it will move slower because as the mass increases, the force of friction between the surface also increases. Thus, the correct option is A.

What is the force of friction?

Force of friction is a type of contact force. Frictional force is the force which resists the motion when the surface of one object comes in contact with the surface of another object. Example of frictional force is the force of friction between two stones which are rubbed with each other. The SI unit of frictional force is Newton (N).

Frictional force can be calculated by the formula:

f = μN

where, f = frictional force,

μ = coefficient of friction,

N = Normal force

The mass of the objects (normal force - mg) which are in motion is directly proportional to the magnitude of the frictional force. As more books are added to the box while the force of push remains same the motion of the box will change and it will move slower because as mass increases, the force of friction between the surface also increases.

Therefore, the correct option is A.

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Geoff counts the number of oscillations of a simple pendulum at a location where the acceleration due to gravity is 9.80 m/s2, and finds that it takes 24.0 s for 14 complete cycles.
1) Calculate the length of the pendulum. (Express your answer to three significant figures.)

Answers

The length of the pendulum is 0.910m if acceleration due to gravity is 9.8 m/[tex]s^{2}[/tex] and it takes 24 s to go 14 cycles.

First we will calculate Time period of pendulum

T = no of oscillations/ time

= 14/24

= 0.5833

We can find length of pendulum using formula

L=g(T/2π)^2

= 9.8(0.583/2×3.14

=9.8(0.583/6.28)

= 0.910 m

A simple pendulum is an arrangement of oscillating bob that has periodic motion. The simple pendulum has a small bob of mass ‘m’ suspended by a thin string fixed to a platform and length of string is L.

The time taken to complete one oscillation is defined as the time period of the pendulum. For simple pendulum of length L , time period is T = 2π √R/2g.

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At a saltwater aquarium, a ray of light strikes the glass, from the air, at an angle of 32° with respect to the normal. The glass has an index of refraction of 1.53. The saltwater has an index of refraction of 1.33. The air has an index of refraction of 1.000293. What is the angle of refraction of the light as it enters the water from the glass?

Answers

20.273° is the angle of refraction of the light as it enters the water from the glass.

What is angle of refraction?

Snell's law states that the angle of refraction, θr, is proportional to the angle of incidence, θi and the ratio of the refractive indices of the two media that comprise the interface. The angle θr=θi and no refraction occur when the mediums have equal refractive indices.

Given that,

Saltwater has an index of refraction = 1.33

The glass has an index of refraction (n₁) = 1.53

Air has an index of refraction (n₂) = 1.000293.

According to Snell's law:

n₂/n₁ = sin θ₁ / sin θ₂

or, 1.000293 / 1.53 = sin θ₁ / sin (32°)

or, 0.6537 = sin θ₁ / 0.52992

or, 0.3465 = sin θ₁

or, θ₁ = sin⁻¹ (0.3465)

or, θ₁ = 20.273°

So, 20.273° is the angle of refraction of the light as it enters the water from the glass.

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An astronaut has landed on an unknown planet. She drops a wrench from a height of 4.07 meters above the surface. The wrench takes 4.97 seconds to fall to the surface. What is the
acceleration of gravity (in meters per second squared) on this planet? Round your answer to two decimal places.

Answers

The acceleration of gravity in the new planet is 0.41 m/s^2.

What is gravitational acceleration?

Gravitational acceleration is the acceleration that an object experiences due to the force of gravity. It is the rate at which an object's velocity changes as it falls toward the center of a gravitational field, such as the Earth or another planet.

The magnitude of gravitational acceleration is often denoted by the symbol "g," and it is equal to the acceleration an object would experience if it were dropped from rest at the surface of the Earth. On the surface of the Earth, g is approximately 9.8 meters per second squared or 1 g. However, the value of g can vary slightly depending on the location and the strength of the gravitational field. For example, g is slightly weaker at the Earth's poles than it is at the equator due to the Earth's slightly oblate shape.

According to the problem:

The acceleration due to gravity on the planet can be determined by the equation:

acceleration = (distance fallen) / (time taken)^2

Substitute 4.07 meters for the distance and 4.97 seconds for the time to determine the acceleration as the following:

acceleration = (4.07 meters) / (4.97 seconds)^2 = 0.41 m/s^2

So the acceleration of gravity on this planet is approximately 0.41 meters per second squared.

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Question 1 options:
Speed is the rate of motion, and velocity contains a ____ of the rate of motion.

Answers

Speed is the rate of motion, and velocity contains a direction of the rate of motion, so the blank space is filled by "direction".

What is velocity?

When anything is moving, its velocity tells us how quickly that something's location is changing from a certain vantage point and as measured by a particular unit of time.

If a point moves along a path and covers a certain distance in a predetermined amount of time, its average speed over that period of time is equal to the distance covered divided by the travel time. A train traveling 100 kilometers in two hours, for instance, is doing it at an average speed of 50 km/h.

Speed is only given the magnitude of the rate of motion, while velocity is given the direction of the rate of motion,

Therefore, Speed is the rate of motion, and velocity contains a direction of the rate of motion.

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What is a balanced force?

A. All applied forces create an equilibrium.
B. All applied forces equal gravity.
C. It keeps an object moving at a changing velocity.
D. When there is no change in direction.

Answers

A balanced force is referred to as when all the applied forces create an equilibrium which is therefore denoted as option A.

What is a Force?

This is referred to as an influence that can change the motion of an object and the formulas is F= ma where m is the mass and a is acceleration of the body involved with its unit being Newton.

Equilibrium on the other hand  is referred to as as a state in which all the individual forces and torques exerted upon an object are balanced and there is no movement of the body in any type of direction in this type of scenario.

Balanced force is referred to as a situation in which all the applied forces which creates an equilibrium as denoted above which is therefore the reason why option A was chosen as the correct choice.

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someone PLEASE help me with this i need it so bad

Answers

The  length of X components is 3,708 and Y component is 11,412

How to calculate X and Y components of the vector?

Another method for locating vector components is to use the angle measured in the opposite direction from the +x axis. Then, the x-component will always be cos and the y-component will always be sin.

A vector's rectangular component Ax, Ay, and Az, respectively, are the projections of vector A along the x, y, and z directions. Space coordinates of a point: The triplet (x, y, z) denotes a point's coordinates.

Given ,

x-component

= 12 * cos 72

= 12 * 0,3090

= 3,708

y component

= 12 . sin 75

= 12 . 0,9510

= 11,412

Therefore The  length of X components is 3,708 and Y component is 11,412

The complete question is : What are the lengths of the x and y components of this vector?

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A block of mass 2kg which is placed on a horizontal surface is pulled by a horizontal force of 50N. What maximum coefficient of static friction is required?
gravity=10m/s2​

Answers

Answer:

The maximum coefficient of static friction required to pull the box will be 0.4.

Explanation:

We have given a box of mass 2 kg and Force of 50 N. (g=10m/s)

As we know,

Coefficient of static friction: μ = F/N (I)(F=ma, a= g)

Putting value in equation (I), we get

μ= mg/

μ=2×10/50

μ=0.4

Light enters a water at an angle of incidence of 24 degree. Calculate the angle of refraction.

Answers

The calculated value of angle of refraction be 29.88°.

What is refraction?

Refraction is defined as "the change in a wave's direction as it passes through a medium."

Although light refraction is one of the most frequently seen phenomena, refraction can also occur with sound and water waves. We can use optical tools like lenses, prisms, and magnifying glasses thanks to refraction. We can focus light on our retina because of the refraction of light, which is another benefit.

Given that;

Angle of incident of light from air to water: i = 24°

Refractive index of water: n = 1.33

So, the angle of refraction be = sin⁻¹(nsini) = sin⁻¹( 1.33 sin24°) = 29.88°.

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Calculate the atmospheric pressure.

Answers

The atmospheric pressure of the sample when depth, density and total pressure is given is 62.5 x 10⁸ Pa.

What is atmospheric pressure?

Atmospheric pressure is defined as a unit of measurement equal to the normalized atmospheric pressure at sea level and 15 °C.  Because it is determined using a barometer, atmospheric pressure is also referred to as barometric pressure.

It can be expressed as

P = hрg

P = 25 x 2.5 x 10⁵ x 1000

P = 62.5 x 10⁸ Pa

Thus, the atmospheric pressure of the sample when depth, density and total pressure is given is 62.5 x 10⁸ Pa.

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Where in the image above is the mass on the spring at its equilibrium position?
At C only
At A and E
Never
At B and D

Answers

The equilibrium position from the above was the position only at the C.

define equilibrium ?

1. A situation when all acting effects are neutralised by other factors, leaving a system that is stable, balanced, or unchanging.

2. Emotional or mental equilibrium.

3. Physics The state of a body or physical system when it is at rest or moving slowly, during which all forces acting on it result in zero and all torques about all axes add up to zero.

4. Chemistry a. A chemical reaction in which both the forward and reverse reactions proceed at the same rate, preventing a change in the concentration of the reactants and products over time.

b. The condition of a system in which there are several phases and interchange between them happens at equal rates, resulting in a net loss of energy.

The sole position at the C was the equilibrium position from the above.

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the basic mental abilities that go into learning and understanding any subject have been classified as
fluid intelligence

Answers

The fundamental mental capacities required to acquire and comprehend any subject have been categorized as fluid intelligence.

Human intelligence includes the abilities to learn from experience, adapt to new situations, understand and manage abstract concepts, and use information to change one's environment. Using longitudinal research designs the same people's behavior is examined over time .  For instance, if we were to examine the connection between intelligence and aging, a scientist might do a longitudinal research to see whether 20-year-olds lose intelligence as they age. Gardner's idea was criticized by Psychologists and teachers. Gardner's concept of intelligence, according to these opponents, is too wide, and his eight different "intelligences" only represent skills, personality traits, and other characteristics.

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a capacitor is charged at a constant charging current of 2.0 x 10^-5A. The time taken to charge the capacitor is 30s and during this time the voltage across the capacitor rises from OV to 12V. What is the capacitance of the capacitor?​

Answers

Answer:

5×10-5 farads

Explanation:

Indications:

Q = charge

I = Current

t = Time

C = Capacitance

V = Voltage

Now, we know, Q = IT = 2×10^-5 ×30 = 6×10^-4 C

again, we know, Q = VC

⇒ C = Q/V = 6×10^-4/12 = 5×10^-5 Farads

A car makes a lab around a 50 m loop in 9 seconds. What his their velocity?

Answers

Answer:

It will 50 m time Taken to complete one round time taken to complete complete one one round, it will nine second. So distance covered in, covered in in one ground equal two prior to that is equal to pi In 250, 1200 five. Now everybody spirit average period equal fear equal distance upon

let x be the number of rolls of a die needed for all 6 numbers to turn up. calculate both the expected value and the variance of x.

Answers

For x be the number of rolls of a die needed for all 6 numbers to turn up then the expected value is 5 and the variance of x is 2.0833 .

But to be absolutely certain, we may apply an even more straightforward procedure to get the solution,

expected value = (1 -p)/p

Where p is the likelihood of success and (1-p) is the expected failure value for the number of rolls of a die needed for all 6 numbers to turn up.

Thus , the 6 number to turn up = p = 1/6

The 6 number to not turn up =(1 - p) = 5/6

Putting the value in above equation we get,

expected value = (1 - 1/6)/1/6 = (5/6)/(1/6)

expected value = 5

Thus, all outcomes on the die between 1 and 6 have an equal likelihood,  the bounds are a = 1, b = 6 ,now calculating the variance of x i.e. V(x)

V(X) = ( b - a)²/12

V(X) = ( 6 - 1)²/12

V(X) = 2.0833

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Four point charges have the same magnitude of 2.4×10^−12C and are fixed to the corners of a square that is 4.0 cm on a side. Three of the charges are positive and one is negative. Determine the magnitude of the net electric field that exists at the center of the square.

Answers

The magnitude of the net electric field at the center of the square is

5.38799 x 10^4 N/C.

What is an electric field?

An electric field is described as the physical field that surrounds electrically charged particles and exerts force on all other charged particles in the field, either attracting or repelling them.

Qa = Charge at point

A = −2.4× 10 −12C

Qb = Charge at point

B = 2.4 × 10 −12C

Qc = Charge at point

C = 2.4×10−12C

Q = Charge at point

D = 2.4 ×10−12C

a= side of the square = 4cm = 0.04 m

Ea = magnitude of the electric field at center of the square due to charge

QAEb

= magnitude of the electric field at center of the square due to charge

QBEc

= magnitude of the electric field at center of the square due to charge

QCEd

= magnitude of the electric field at center of the square due to charge

QDE x = Net electric field in X-axis.

Ey

= Net electric field in Y-axis

Magnitude of electric field at distance R due to a charge q = kx q/R^2

Where k = 8.98 X 10^9

Magnitude of net electric field in X-axis is

Ex = Ea×cos45 + Ec × cos45 +Eb × cos45 − Ed × cos45

Ex =

3.80989 × 10^4 N/C (If you substitute values)

Magnitude of net electric field in Y-axis is

Ex = Ea× Sin45 + Ec × Sin45 +Eb × Sin45 − Ed × Sin45

Ex =  5.38799 × 10^4 N/C

Therefore, the magnitude of the net electric field at the center of the square is

5.38799 x 10^4 N/C.

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large dorm, half the rooms are randomly wired for high-speed internet connections (the treatment group), and final course grades are collected for all residents. Which of the following pose threats to internal validity, and why? a. Midway through the year all the male athletes move into a fraternity and drop out of the study (their final grades are not observed). b. Engineering students assigned to the control group put together a local area network so that they can share a private wireless internet connection that they pay fo

Answers

Answer:

HAHAHAHAHAHAHAHAH

Explanation:

HAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAAHAHAHAHAH

The image below shows an onion root viewed under a microscope.

What does this image best demonstrate?
A.
Living organisms are composed of one or more cells.
B.
Cells of different organisms have a similar composition.
C.
New cells only arise from pre-existing cells.
D.
Each cell can perform all functions necessary for life.

Answers

Answer:

Explanation:

a

As an object moves from point A to point B only two forces act on it: one force is conservative and does -70 J of work, the other force is nonconservative and does +50) of work. Between A and B, A) the kinetic energy of object decreases, mechanical energy decreases.B) the kinetic energy of object increases, mechanical energy increases. C) the kinetic energy of object increases, mechanical energy decreases D) the kinetic energy of object decreases E) mechanical energy increases

Answers

As the object moves from point A to B, the kinetic energy of the object decreases and the mechanical energy of the object increases.

In this problem, the law of energy conservation is applied. It is given that the work done by conservative force is -70J and the work done by non-conservative force is 50J.

The resulting forces between these two forces is -70J + 50J = -20 J.

The conservative force is linked with the movement caused by the sum of two energies, therefore there is a decrease in kinetic energy. The increase in mechanical energy is due to the positive non-conservative force.

Thus, the correct answer is kinetic energy of the object decreases and the mechanical energy increases.

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If you keep a gas's temperature constant, how would you increase the volume of the gas?

a
You would change the temperature
b
You would increase the pressure
c
You would decrease the temperature
d
You would decrease the pressure

Answers

when the temperature is kept constant, to increase the volume of the gas, you will decrease the pressure (Option D)

How do I increase the volume at constant temperature?

The volume of a gas at constant temperature is explained by the Boyle's law equation which is states as follow:

The volume of a fixed mass of gas is inversely proportional to the pressure at conctant temperature. Mathematically, it is expressed as follow:

P ∝ = 1/V

P = K / V

P₁V₁ = P₂V₂

Where

P₁ and P₂ are initial and new pressure V₁ and V₂ are initial and new volume

From the above formula, we can see that volume and pressure exist in inverse proportionality. This means that when the volume increases, the pressure will decrease and also, when the volume decreases, the presure will increase.

With the above information, we can conclude that the correct answer to the question is: You would decrease the pressure (Option D)

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The weight of a synthetic ball varies directly with the cube of its radius. A ball with a radius
of 2 inches weighs 2.00 pounds. Find the weight of a ball of the same material with a
3-inch radius.
The weight of a ball of the same material with a 3-inch radius is
(Type an integer or a decimal.)
lb.

Answers

The weight of a ball of the same material with a 3-inch radius is 12.15 pounds.

What is weight?

All things close to Earth are constantly subject to the force known as weight. All items are pulled downward toward the Earth's center by the gravity of the planet.

As a result, kilograms times meters per second squared, which is equivalent to a newton, can be used to quantify weight in the SI (N).

Weight can be expressed using the formula W = m*g, where weight can be expressed as kg * m/s2, which is equivalent to N, since weight is the force that gravity extends on a mass.

Let w equal the ball's weight in pounds.

r is the spherical ball's radius in inches.

The constant, C, converts the connection into a formula and ensures that the units are calculated correctly.

So, w = C r 3.

First determine C using the 2 "example: C= w/r3 = 3.60/(2)3 = 3.60/8 = 0.45

Now that you know C, you can determine the larger 3's weight "ball:

w = 0.45 r3 = 0.45

3  = 0.45 (27) = 12.15 pounds

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some students want to calculate the work done by friction as an object with unknown mass moves along a straight line on a rough horizontal surface. the students have a force probe, a meterstick, and a stopwatch. which of the following will allow the students to take the measurements needed to calculate the work done by friction?

Answers

Pulling the block at an unknown constant acceleration with the force probe for a measured distance will allow the students to take the measurements needed to calculate the work done by friction. the correct answer is C.

As is common knowledge, the product of force and displacement defines the amount of work done.

hence, it is said as

W =F.d

where,

W is work

F is force

D is displacement

Therefore, in this case, force and displacement must be known in order to determine the work done.

In order to determine the amount of work done, we must first pull the block with a constant acceleration. therefore the correct answer is C

Your question is incomplete but most probably your full question was

Some students want to calculate the work done by friction as an object with unknown mass moves along a straight line on a rough horizontal surface. The students have a force probe, a meterstick, and a stopwatch. Which of the following will allow lo lake the measurements needed to calculate the work done by friction?

(A) Pulling the block at an unknown constant acceleration with the force probe for a measured time.

(B) Pulling the block at an unknown constant speed with the force probe for a measured time.

(C) Pulling the block at an unknown constant acceleration with the force probe for a measured distance.

(D) Pulling the block at an unknown constant speed with the force probe for a measured distance.

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Q13: Which distance P, Q, R, or S, represents the amplitude of the wave below?

Answers

Answer:

The answer is S

Explanation:

Amplitude is defined as the height of a wave from its undisturbed level.

A 650 kg elevator starts from rest. It moves upward for 4.50 s with constant acceleration until it reaches its cruising speed, 1.75 m/s.
(a) What is the average power of the elevator motor during this period? W
(b) How does this power compare with the motor power when the elevator moves at its cruising speed? Pcruising = W

Answers

5789.8 W  is the average power of the elevator motor during this period and 1.115 * 10⁴ W this power compare with the motor power when the elevator moves at its cruising speed.

What is an explain acceleration?

The rate with which the speed and direction of a moving object vary over time. A point a object going straight ahead is pushed when it accelerates or decelerates.

Briefing:

Mass of elevator = 650 kg

Time = 4.50 sec

Speed of the elevator = 1.75 m/s

Calculating the elevator's acceleration is necessary.

Using the acceleration formula

a = vf - vi / t

a = 1.75 / 4.50

a = 0.38 m/s2

(a). We must determine the net force acting on the elevator.

Using the force formula

T = mg + ma

T = m (g +a)

T = 650 (9.8 + 0.38)

T = 6617 N

We must determine the average velocity.

Using the average velocity formula

v' = vf + vi / 2

v' = 1.75 / 2

v' = 0.875 m/s

We must determine the average power.

Using the power formula

P = T * v'

P = 6617 * 0.875

P = 5789.8 W

(b). We must determine the motor's power input.

Using the power formula

P = F * v

P = mg * v

P = 650 * 9.8 * 1.75

P = 1.115 * 10⁴ W.

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