4. A weightlifter lifts a set of weights a vertical distance of 2 meters. If a constant net force of 350 N is exerted on the weights, what is the net work done on the weights?

Answer:

Approximately [tex](-348\; {\rm J})[/tex], assuming that the bike was on level ground.

Explanation:

If an object of mass [tex]m[/tex] is moving at a speed of [tex]v[/tex], the kinetic energy of that object would be [tex](1/2)\, m\, v^{2}[/tex].

At a speed of [tex]v = 3.84\; {\rm m\cdot s^{-1}}[/tex], the kinetic energy of the bike and the cyclist- combined- would be:

[tex]\begin{aligned} &\frac{1}{2}\, m\, v^{2} \\=\; &\frac{1}{2}\times 53.0\; {\rm kg} \times (3.84\; {\rm m\cdot s^{-2}})^{2} \\ \approx \; & 390.76\; {\rm J}\end{aligned}[/tex].

At a speed of [tex]v = 1.27\; {\rm m\cdot s^{-1}}[/tex], the kinetic energy of the bike and the cyclist- combined- would be:

[tex]\begin{aligned} &\frac{1}{2}\, m\, v^{2} \\=\; &\frac{1}{2}\times 53.0\; {\rm kg} \times (1.27\; {\rm m\cdot s^{-2}})^{2} \\ \approx \; &42.741 \; {\rm J}\end{aligned}[/tex].

The energy change was approximately:

[tex]390.76\; {\rm J} - 42.741\; {\rm J} \approx 348\; {\rm J}[/tex].

If the bike was on level ground, the friction on the bike and the cyclist would have done a work of [tex](-348\: {\rm J})[/tex] to reduce the kinetic energy of the bike and the cyclist by that amount.

Answer: C) -348J

Explanation:

42.741 - 390.76 (the kinetic energy of the two speeds) is equal to -348.

The current flowing in resistor 1 in the given series circuit is determined as 1.0 A.

The equivalent resistance of the circuit is determined as follows;

Rt = R1 + R2

Rt = 15 + 5

Rt = 20ohms

The current flowing in the circuit is determined from Ohm's law.

V = IR

I = V/R

I = 20/20

I = 1.0 A

since it is series circuit, same current will flow in R1 and R2.

Thus, the current flowing in resistor 1 in the given series circuit is determined as 1.0 A.

Learn more about current here: https://brainly.com/question/24858512

#SPJ1

If you had a 14 m long timeline, the dinosaurs would be less than one meter from the end.

The extinction of species or organisms is the process by which some environmental factors cause a decline in the number of species through death.

Dinosaurs are some of the examples of species that are in extinct.

Since dinosaurs are in extinction, If you had a 14 m long timeline, the dinosaurs would be less than one meter from the end.

Learn more about extinction here: https://brainly.com/question/1048615

#SPJ1

Considering the definition of velocity, the average velocity of Ben is 0.3 [tex]\frac{meters}{second}[/tex].

Velocity is a physical magnitude that relates the displacement of an object, the time it takes to make this change in position and direction.

Because the speed also considers the direction in which the displacement of an object occurs, it is considered a vector magnitude.

So, the velocity can be defined as the amount of space traveled per unit of time with which a body moves, considering the direction, and can be calculated using the expression:

[tex]velocity=\frac{distancetraveled}{time}[/tex]

Velocity has units of [tex]\frac{distance}{time}[/tex], such as [tex]\frac{meters}{second}[/tex] or [tex]\frac{meters}{minute}[/tex], and includes direction of travel.

Ben walks 500 meters from his house to the corner store. He then walks back toward his house, but continues 200 meters past his house to talk to a neighbor.

So, you know:

Replacing in the definition of velocity:

[tex]velocity=\frac{300 meters}{1020 seconds}[/tex]

Solving:

velocity= 0.3 [tex]\frac{meters}{second}[/tex]

Finally, the average velocity of Ben is 0.3 [tex]\frac{meters}{second}[/tex].

Learn more about velocity:

brainly.com/question/4418301

brainly.com/question/24990123

brainly.com/question/14244558

brainly.com/question/25288184

#SPJ1

Answer:

gravity

Explanation:

Given that the linear expansion of the pipe is 12×10¯⁶ K¯¹, the pipe extends by 0.024 mm

α = ΔL / L₁ΔT

12×10¯⁶ = ΔL / (100 × 20)

12×10¯⁶ = ΔL / 2000

Cross multiply

ΔL = 12×10¯⁶ × 2000

ΔL = 0.024 mm

Learn more about linear expansion:

https://brainly.com/question/23207743

#SPJ1

The increase in velocity of the student per second is 10 m/s^2 and her change in momentum each second is 500 kgm/s^2.

The change in velocity of a moving object is known as acceleration.

For any object falling freely under gravity, the change in velocity per second or acceleration due to gravity is a constant and is equal to 10 metres per square second (10 m/s^2).

The change in momentum of a body is given as follows:

where m is mass, v is final velocity and u is final velocity.

Mass of the student = 50 Kg

Change in momentum each second = 50 kg × 10 m/s^2 = 500 kgm/s^2

Therefore, the increase in velocity of the student per second is 10 m/s^2 and her change in momentum each second is 500 kgm/s^2.

Learn more about change in momentum at: https://brainly.com/question/27778439

#SPJ1

Answer:

It loses potential energybut gains kinetic energy.

Explanation:

From the calculations, the absolute refractive index of the material is 0.6.

The refractive index is the ratio of the sine of the angle of incidence to the sine of the angle of refraction.

Having looked at the path of the travelling light wave, we can see that the absolute refractive index of the ray of light is; sine 27/sin 49 = 0.454/0.755

= 0.6

Learn more about refractive index:https://brainly.com/question/23750645

#SPJ1

A solenoid has 18 turns per centimeter of its length. the solenoid is twisted into a circle so that it becomes shaped like a toroid, the magnetic field at the center of each turn of the toroid is mathematically given as

B=3.39292007×10^−5 T

Generally, the equation for magnetic field is mathematically given as

B=\mu_0 * n *I

Where

n=18

n=1800turns/m

Therefore

B=4*\pi*10^{-7}*1800*15*10^{-3}

B=3.39292007×10^−5T

In conclusion, the magnetic field at the center of each turn of the toroid is

B=3.39292007×10^−5T

Read more about  magnetic field

https://brainly.com/question/7802337

#SPJ1

Answer:

Force of gravity.

So I think it's the gravity option?

Gravity keeps earth and other objects in the solar system from spinning off into outer space.

The force that pulls objects towards the center of a planet or other body is known as gravity.

Here,

Since it depicts the interaction that results when two masses are in close proximity, gravity is in fact a force. The warping of spacetime and the motion of things through the stretched spacetime are the primary causes of gravitational effects.

It appears as though a force was exerted towards the end, though.

The force that pulls objects towards the centre of a planet or other body is known as gravity. All of the planets are kept in orbit around the sun by the force of gravity.

We are confined to the surface of the Earth by gravity alone. Size, mass, density, and composition of planets are all quantifiable characteristics. The gravitational pull of a planet is determined by its size and mass.

Hence,

Gravity keeps earth and other objects in the solar system from spinning off into outer space.

To learn more about gravity, click:

https://brainly.com/question/14874038

#SPJ2

Based on the calculations, the speed of this roller coaster at the bottom of the hill is equal to: B. 39.6 m/s.

Given the following data:

Height = 80.0 meters.

Scientific data:

Acceleration due to gravity (g) = 9.8 m/s².

In accordance with the law of conservation of energy, the potential energy possessed by the roller coaster at the top is equal to the kinetic energy possessed by the roller coaster at the bottom of the hill:

PE = KE

mgh = ½mv²

2mgh = mv²

v = √(2gh)

Substituting the given parameters into the formula, we have;

v = √(2 × 9.8 × 80)

v = √1,568

Speed, v = 39.6 m/s.

Read more on potential energy here: https://brainly.com/question/1242059

#SPJ1

Answer:

your hand will be heat you will feel small pain inside your hand

(a) The spring stiffness constant of the spring is 18,392 N/m.

(b) The time the car was in contact with the spring before it bounces off in the opposite direction is 0.23 s.

The kinetic energy of the car is calculated as follows;

K.E = ¹/₂mv²

K.E = ¹/₂ x 950 x 22²

K.E = 229,900 J

The stiffness constant of the spring is calculated as follows;

K.E =  U = ¹/₂kx²

k = 2U/x²

k = (2 x 229,900)/(5)²

k = 18,392 N/m

F = kx

F = 18,392 x 5

F = 91,960 N

F = mv/t

t = mv/F

t = (950 x 22)/(91960)

t = 0.23 s

Learn more about spring constant here: https://brainly.com/question/1968517

#SPJ4

Answer:

Discuss Your Presentation With an Expert

1) Skip the Stock Template.

2) Don't Use More than 6 Lines of Text.

3) Ditch the Bullet Points.

4) Use Sans Serif Fonts.

5) Size Fonts Appropriately.

6) Maintain a Strong Contrast Between Text and Background.

7) Use No More than 5 Colors.

8) Use Contrasting Text Colors to Draw Attention.

Answer:

See below

Explanation:

KE = 1/2 m v^2     multiply both sides by 2

2 (KE) = mv^2       divide both sides by m

2(KE) / m = v^2        sqrt both sides

√ [(2KE)/m ] = v

The student 4 measurement has the largest percent error. The discrepancy between the calculated value and the correct value is referred to as an "error" in statistics.

An error is a mistaken or erroneous action. In some contexts, an error is interchangeable with a mistake.

The complete question is

'Four students measured the acceleration of gravity. The accepted value for their location is 9.78m/s2. Which student’s measurement has the largest percent error?

A. Student 4: 9.61 m/s2

B. Student 3: 9.88 m/s2

C. Student 2: 9.79 m/s2

D. Student 1: 9.78 m/s2"

The percentage error is found as;

[tex]\rm \% error = \frac{a_A-a_E}{a_E} \times 100[/tex]

The percentage error in the gIven four students is obtained by putting the values in the given problem;

Student 1 ;

[tex]\rm \% error = \frac{9.78-9.78}{9.88}\times 100 \\\\\ \% error = 0 \%[/tex]

Student 2 ;

[tex]\rm \% error = \frac{9.78-9..79}{9.79}\times 100 \\\\\ \% error = - 0.10 \%[/tex]

Student 3 ;

[tex]\rm \% error = \frac{9.78-9.88}{9.88}\times 100 \\\\\ \% error = - 1.01 \%[/tex]

Student 4 ;

[tex]\rm \% error = \frac{9.78-9.61}{9.61}\times 100 \\\\\ \% error =1.77\%[/tex]

Student 4 reports the maximum percentage error.

Hence the student 4 measurement has the largest percent error.

To learn more about the error refer to the link;

https://brainly.com/question/13286220

#SPJ1

Answer:

A

Explanation:

when  area increases pressure decrease

for example, a sharp nail's area is lower than a blunt nail, so sharp nail is easy to fix

so, here a exerts more pressure

Answer:

a

Explanation:

The likely outcome when a magnetically soft material is placed in a strong magnetic field is that it will become a temporary magnet because the domains will easily realign.

A magnet is a material whose magnetic domains are properly aligned. These materials are able to attract other materials that are magnetizable.

Hence, the likely outcome when a magnetically soft material is placed in a strong magnetic field is that it will become a temporary magnet because the domains will easily realign.

Missing parts:

A magnetically soft material is placed in a strong magnetic field. What is the most likely outcome?

a. It will become a permanent magnet because the domains will remain aligned.

b. It will become a temporary magnet because the domains will remain aligned.

c. It will become a permanent magnet because the domains will easily realign.

d. It will become a temporary magnet because the domains will easily realign.

Learn more about magnets:https://brainly.com/question/14301573

#SPJ1

Answer: D or It will become a temporary magnet because the domains will easily realign.

Explanation: Taking the quiz!

According to Newton's first law of motion, the puck gradually slows down because friction would be acting on it.

Newton's first law of motion states that an object will remain at rest or move uniformly in a straight line unless acted upon by an external force.

According to this question, a hockey puck is hit with a large force. The puck moves at a high speed as it slides over the ice.

However, in accordance with the first law of motion proposed by Newton, the puck gradually slows down because friction would be acting on it.

Learn more about Newton's law at: https://brainly.com/question/974124

#SPJ1

Answer:B. The puck gradually slows down because friction would be acting on it.

Explanation:

The force of the person is 68 N away from the wall.

Force is the product of mass and acceleration.

To calculate the force used by the person to push the wall, we use the formula below.

Formula:

Where:

From the question,

Given:

Substitute these values into equation 1

Hence, the force of the person is 68 N away from the wall.

Learn more about force here: https://brainly.com/question/12970081

#SPJ1

The ratio of the area of the plunger to the area of the piston will be 0.2323.

The force applied perpendicular to the surface of an item per unit area across which that force is spread is known as pressure.

It is denoted by P. The pressure relative to the ambient pressure is known as gauge pressure.

The presure at the output remains the same

[tex]\rm P_0=P_I \\\\\ \frac{F_0}{A_o} =\frac{F_I}{A_I} \\\\ \frac{A_0}{A_I} = \frac{F_0}{F_I} \\\\ \frac{A_0}{A_I} =\frac{39}{1675} \\\\ \frac{A_0}{A_I} =0.2323[/tex]

Hence, the ratio of the area of the plunger to the area of the piston will be 0.2323.

To learn more about the pressure refer to the link;

https://brainly.com/question/356585

#SPJ1

Heating and Cooling Using Geothermal Heat, Natural Air Conditioning. Another use of this type of energy is natural cooling.Maintenance of Civil Works. Another direct application is to avoid the freezing of bridges, roads, or airports. .Thermal Waters. For the use of heat in hot springs from geothermal energy, deep waters with temperatures between 40 and 150 ° C are used.

A ball held over a person's head | a ball rolling on the floor is an example of an object that has potential energy followed by an object that has kinetic energy.

This is the type of energy possessed by a body by virtue of its motion or movement.

The rolling ball therefore has kinetic energy while a ball being held over a person's head has potential energy which is the energy possessed by a body by virtue of its position.

Read more about Kinetic energy here https://brainly.com/question/8101588

#SPJ1

Atoms cannot be broken down into smaller pieces is the statement belongs to daltons atomic theory. Option B is correct.

The atom consists of matter that may be split without releasing electrical charges. It's also the smallest unit of matter with chemical element features.

The complete question is:

"Which statements belong to Dalton's atomic theory? Select all that apply.

A)Atoms cannot be created or destroyed.

B)Atoms cannot be broken down into smaller pieces.

C)All atoms of an element are identical.

D)Chemical reactions cause atoms to be rearranged."

According to Dalton's atomic hypothesis, atoms cannot be broken down into smaller bits.

Hence, option B is correct.

To learn more about the atom refer to the link;

https://brainly.com/question/1566330

#SPJ1

Answer:

[tex]2.8\; {\rm s}[/tex].

Explanation:

The velocity of vehicle [tex]2[/tex] relative to vehicle [tex]1[/tex] is:

[tex]\begin{aligned}& \text{velocity of 2 relative to 1} \\ =\; & (\text{velocity of 2 relative to ground}) \\ &- (\text{velocity of 1 relative to ground}) \\ =\; & 33\; {\rm m\cdot s^{-1} - 28\; {\rm m\cdot s^{-1}} \\ =\; & 5\; {\rm m\cdot s^{-1}} && (\text{to the east})\end{aligned}[/tex].

The displacement of vehicle [tex]2[/tex] relative to vehicle [tex]1[/tex] is currently [tex]0\; {\rm m}[/tex]. The rate at which this displacement increases is equal to the velocity of vehicle [tex]2\![/tex] relative to vehicle [tex]1\![/tex], which is [tex]5\; {\rm m\cdot s^{-1}}[/tex].

Thus, it would take [tex](14 \; {\rm m}) / (5\; {\rm m\cdot s^{-1}}) = 2.8\; {\rm s}[/tex] for this displacement to reach [tex]14\; {\rm m}[/tex].

Answer:  B

Explanation:  AN increase in heat out

(a) The time it takes for the police officer to catch up to the speeding car is determined as 0.31 s.

(b) The speed of the police officer  at the time he catches up to the driver is 136.8 km/h.

The time taken for the police to catch up with the driver is calculated as follows;

v = at

where;

t = v/a

t = 37.5/3.278

t = 11.4 seconds

(v1 - v2)t = ¹/₂at² --- (1)

(v1 - v2)t = v1²/2a --- (2)

From (1):

(v1 - 37.5)t = ¹/₂(3.278)t²

(v1 - 37.5)t = 1.639t²

v1 - 37.5 = 1.639t

v1 = 1.639t + 37.5  -----(3)

From (2):

(v1 - 37.5)t = v1²/(2 x 3.278)

(v1 - 37.5)t = 0.153 ----- (4)

solve 3 and 4;

(1.639t + 37.5 - 37.5)t = 0.153

1.639t² = 0.153

t² = 0.0933

t = 0.31 s

v1 = 1.639(0.31) + 37.5 = 38 m/s = 136.8 km/h

Learn more about velocity here: https://brainly.com/question/4931057

#SPJ1

Taking into account the Boyle's law, the new pressure in the balloon is 120 000 Pa.

Boyle's law establishes the relationship between the pressure and the volume of a gas when the temperature is constant.

Boyle's law states that the pressure of a gas in a closed container is inversely proportional to the volume of the container, when the temperature is constant: if the pressure increases, the volume decreases, while if the pressure decreases, the volume increases.

Mathematically, this law says that if the amount of gas and the temperature remain constant, the product of pressure times volume always has the same value:

P×V= k

Now it is possible to assume that you have a certain volume of gas V1 which is at a pressure P1 at the beginning of the experiment. If you vary the volume of gas to a new value V2, then the pressure will change to P2, and the following is true:

P1×V1=P2×V2

In this case, you know:

Replacing in the Boyle's law:

100 000 Pa×0.030 m² =P2×0.025 m²

Solving:

(100 000 Pa×0.030 m²) ÷0.025 m²= P2

120 000 Pa= P2

Finally, the new pressure in the balloon is 120 000 Pa.

Learn more about Boyle's law:

https://brainly.com/question/4147359

#SPJ1