What is the normal force and gravitational force on a 55 kg person standing stationary?
Answer:
539.55 N for both
Explanation:
F=ma
Mass is given at 55kg
And when finding gravitational force gravity's constant is an acceleration of 9.81m/s
F=(55)(9.81)
F= 539.55 N (for both)
Normal force cancels out gravitational force that's why we don't fall throught the floor.
We push down on the floor due to gravitational force but normal force keeps us upright pushing an equal amount back.
What is a core sample?
Answer:
it's a part of plate that moves with a plate that's the answer
20 POINTS:
Why does the initial hill of a roller coaster need to be steep?
Answer: A roller coaster does not have an engine to generate energy. The climb up the first hill is accomplished by a lift or cable that pulls the train up. This builds up a supply of potential energy that will be used to go down the hill as the train is pulled by gravity
Hope this helps! Good luck with future homework and exams!
Ron weighs a bottle with a mass of 0.5 kilograms on a spring scale. The spring stretches by 1 centimeter. He then weighs a second bottle on the same spring scale. What is the mass of the second bottle, in kg, if the spring stretches by 2 cm
Answer:
1 kg
Explanation:
Applying,
Hook's law,
F = ke................. Equation 1
Where F = force, k = force constant of the spring, e = extension.
But from the question,
The weight of the bottle is the force acting on the spring scale
therefore,
mg = ke............ Equation 2
Where m = mass of the bottle, g = acceleration due to gravity.
make k the subject of the equation
k = mg/e............ Equation 3
Given: m = 0.5 kg, e = 1 cm = 0.01 m
Constant: g = 9.8 m/s²
k = (0.5×9.8)/0.01
k = 490 N/m
If the mass of the second bottle is weighed,
given: e = 2 cm = 0.02 m
subtitute into equation 1
m×9.8 = 490×0.02
9.8m = 9.8
m = 9.8/9.8
m = 1 kg.
Hence the mass of the second bottle is 1 kg
‘The Universe is expanding.’ Justify this statement with the Big bang model of universe and Hubble’s Law.
Explanation:
The expansion of the universe is the increase in distance between any two given ... Metric expansion is a key feature of Big Bang cosmology, is modeled mathematically with the ...
A charge Q creates an electric field. At a distance of 10 cm, the electric field strength
is 30 N/C. What is the electric field strength at a distance of 20 cm? NO LINKS.
1) 7.5 N/C
2) 15 N/C
3) 60 N/C
4) 120 N/C
Answer:
simltinoues divide two eqn El÷E2 Kq\ r^2\kq \2r^2 then you get it 7.5 N\c the answer is A
What if the World turned to Gold?
Answer:
We would all freeze at close to absolute zero and gold will not be worth anything
Explanation:
Reason whether or not work is done in the following cases:
A. a basketball player shoots a free throw.
B. a peasant pulls a rope tied to a donkey without being able to displace it from its position.
Answer:
A work is done because the object moved
B no work is done because the donkey didnt move
Explanation:
A 9 kg box is placed on a 6 m tall shelf. What will be the kinetic energy of the box right before it hits the ground? (use g = 10 m/s/s)
Answer:
540 J
Explanation:
U at top equals to K at bottom if it's an isolated system therefore U at top is equals to 540 J so we can assume that at 0m U=0 (mgh) therefore the box has gained some velocity due to the acceleration due to g and we can calculate it using 1/2mv²
The ship was travelling 93 meters per second, 25 degrees above the x-axis Northeast. Determine the magnitude and direction of the horizontal vector component, Vx.
Answer: [tex]92.18\ m/s[/tex], east
Explanation:
Given
Ship is traveling at a speed of [tex]v=93\ m/s[/tex]
Direction of ship is [tex]25^{\circ}[/tex] North of east
If we break velocity vector in x and y axes then, the horizontal component is given by
[tex]\Rightarrow v_x=93\cos 25^{\circ}\\\Rightarrow v_x=92.18\ m/s[/tex]
The direction of horizontal component is towards east with magnitude of [tex]92.18\ m/s[/tex]
The equivalent resistance of a complex circuit is usually determined by a dividing the sum of the individual resistances by the number of resistances. b adding and subtracting individual resistances. c inspection. d simplifying the circuit into groups of series and parallel circuits.
Answer:
d
Explanation:
we simplify the circuit into groups to obtain a complete circuit I.e series and parallel circuit
a toy car takes .60 seconds to travel .30 meters after it is released from rest. what is the acceleration of the toy car?
A positive charge is moving across a room from south to north. A magnetic field runs from east to west. In what direction is the magnetic force on the moving positive charge?
Answer:
the force is on the z axis, coming out of the blade
Explanation:
The direction of the magnetic force is given by the right hand rule,
For a positive charge, the thumb points in the direction of velocity, the other fingers extended in the direction of the magnetic field, and the palm points in the direction of force.
In this case.
Thumb points North
The fingers extended is in the east - west direction parallel to the blade
The palm is sticking out of the leaf, in the z direction
the answer is the force is on the z axis, coming out of the blade
1. I get so much energy when I eat candy! What type of energy is this statement referring to?
O mechanical
O kinetic
O potential
O chemical
The answer is chemical
What does the geology of the two continents indicate about past events in Earth history?
Answer:
Explanation:
Rocks tell us a great deal about the Earth's history. Igneous rocks tell of past volcanic episodes and can also be used to age-date certain periods in the past. Sedimentary rocks often record past depositional environments (e.g deep ocean, shallow shelf, fluvial) and usually contain the most fossils from past ages.
Which is the preserved evidence of the activity of an organism?
Answer:
Fossils are the remains of an ancient organism or the traces of activity of such an organism. There are two types of fossils: body fossils and trace fossils. Body fossils include preserved remains of an organism (i.e. freezing, drying, petrification, permineralization, bacteria and algea).
The force between two charges is 1000 N. One has a charge of 2.0 x 10-5 C and one has a charge of 5.0 x 10-6 C. What is the distance between the charges?
Answer:
F= kq1q2÷r^2 r=√9x10^9 x 2.0 x 10^-5 x 5.0x 10^-6 ÷ 1000 ) the ansewer√300
A blow-dryer and a vacuum cleaner each operate with a voltage of 120 V. The current rating of the blow-dryer is 14 A, while that of the vacuum cleaner is 4.2 A. Determine the power consumed by (a) the blow-dryer and (b) the vacuum cleaner. (c) Determine the ratio of the energy used by the blow-dryer in 16 minutes to the energy used by the vacuum cleaner in 43 minutes.
Answer:
The correct solution is:
(a) 1680 W
(b) 504 W
(c) 1.240
Explanation:
The given values are:
Voltage,
V = 120 V
Current of blow dryer,
I₁ = 14 A
Current of vacuum cleaner,
I₂ = 4.2 A
Time,
t₁ = 16 min
t₂ = 43 min
As we know,
⇒ [tex]Power (P) = VI[/tex]
(a)
For blow dryer:
⇒ [tex]P_1=V\times I_1[/tex]
[tex]=120\times 14[/tex]
[tex]=1680 \ W[/tex]
(b)
For Vacuum cleaner:
⇒ [tex]P_2=V\times I_2[/tex]
[tex]=120\times 4.2[/tex]
[tex]=504 \ W[/tex]
(c)
The ratio will be:
= [tex]\frac{Blow \ dryer \ energy}{Vacuum \ cleaner \ energy}[/tex]
= [tex]\frac{P_1\times t_1}{P_1\times t_2}[/tex]
= [tex]\frac{1680\times 16}{504\times 43}[/tex]
= [tex]\frac{26880}{21672}[/tex]
= [tex]1.240[/tex]
The firing of a bullet by a rifle causes the rifle to recoil backwards. The speed of
the rifle's recoil is smaller than the bullet's forward speed because the___
A.)force against the rifle is relatively small
B.)speed is mainly concentrated in the bullet
C.)rifle has lots of mass
D.)momentum of the rifle is unchanged
Answer:c i.e. rifle has lots of mass
Explanation:It's because we know that the force of recoiling is same. But since the mass of rifle is very much greater than that of the bullet, it's balanced by the less speed of the recoiling of the rifle.
Which of the following has the most kinetic energy?
A. A 25-kg fish tank sitting on a table
B. A 50-g fish swimming in a fish tank
C. A 7,500-kg car parked on a steep hill
D. A 50-kg Boulder suspended from a cliff
Answer:
The answer is B
Explanation:
Only things that are moving have kinetic energy, therefore B is the only correct answer
Juan's mother drives 12.5 miles southwest to her favorite shopping mall. What is the velocity of her
automobile if she arrives at the mall in 7.25 minutes?
Answer:
v1= 12.5miles, t= -7.25m, a= 0
v= 1/2at^2
v= 1/2×
A small object is launched with a velocity 26.2 m/s at an angle 35.8 degrees above the horizontal from the top of a building with height 46.4 m. Air resistance is negligible during the motion of the object. How long (in seconds) does it take the object to reach the ground
Answer:
Explanation:
The angle here makes this a very interesting problem. We will use only the y-dimension information since we are given nothing pertinent in the x-dimension. Nothing there is useful to solving this problem. We are given (and know from experience) the following:
θ = 35.8°
v₀ = 26.2 m/s
Δx = -46.4 m
a = -9.8 m/s/s
t = ???
Time is our main unknown. The displacement is negative because, in the end, the small object will end up BELOW the point from which it is launched. That's important!!
Another thing we need to understand is that the velocity we are given is a "blanket" velocity; it is neither the upwards velocity nor the horizontal velocity. That's for us to find out using either cos or sin. In the y-dimension, we use the sin identity to find the upwards velocity (which is VERY different from the horizontal velocity {unless we are dealing with a 45 degree angle where sin and cos are the same}). So first we need to find the initial velocity in this dimension specifically:
26.2sin35.8 = 15.3 m/s
That's the initial velocity we will use in the problem now. The equation for this is:
Δx = v₀t + [tex]\frac{1}{2}at^2[/tex] and filling in the given info:
[tex]-46.4=15.3t+\frac{1}{2}(-9.8)t^2[/tex] It looks like this will have to be factored if we are going to solve for t. Get everything on one side and factor the resulting quadratic:
[tex]-4.9t^2+15.3t+46.4=0[/tex] and factoring that gives you 2 values for t:
t = -1.9 sec and t = 5.0 sec
Since we all know that time can NEVER be negative, t = 5.0 sec.
A beam of light hits a mirror at an angel of 35 degrees. What is the angel that it bounces off at?
a. 55 degrees
b. 35 degrees
c. 90 degrees
Answer:
c
Explanation:
light refraction is a right angle
A beaker containing water at 80°C is placed on a piece of aluminum at 25°C. How will thermal energy transfer? O by conduction from the aluminum to the beaker O by convection from the aluminum to the beaker O by convection from the beaker to the aluminum O by conduction from the beaker to the aluminum
The thermal energy transfer will occur by convection from the aluminium to the beaker.
Thermal energy can be defined as the energy held in a system that is accountable for the overall temperature of the system.
Conduction is the process by which heat energy is transferred from one material or substance to another.
Convection is the transfer of heat in the fluid medium. e.g when a fluid is heated, heat energy is transferred into the fluid which causes a rise in the temperature of the fluid.
Since water is a fluid medium, the thermal energy transfer will occur by convection from the aluminium to the beaker.
Learn more about thermal energy here:
https://brainly.com/question/7541718
What is the equation for density? NO LINKS
d = V/m
d= m + V
d= m x V
d= m/V
If a roller-coaster car has 40,000 J of gravitational potential energy when at rest on the top of a hill, how much kinetic energy does it have when it is ½ of the way down the hill?
=============================================
Work Shown:
PE = potential energy
KE = kinetic energy
m = mass
g = acceleration of gravity
h = height of the object
PE = m*g*h = 40,000 joules
---------
If the car is halfway down the hill, then that means the height of the car is h/2 instead of h
We can then say:
m*g*(h/2) = (m*g*h)/2 = (40,000)/2 = 20,000 J
is the amount of potential energy at this location. The amount of kinetic energy must be the remaining amount that adds to this, to get 40,000 J again.
Put another way: The 40,000 J of PE to start off with, when KE = 0, means we have a total energy of 40,000 J
---------
So,
PE+KE = total energy
PE+KE = 40,000 J
20,000 J + KE = 40,000 J
KE = (40,000 J) - (20,000 J)
KE = 20,000 J when the car is halfway down the hill.
Iron meteorites are interpreted as deriving from the cooled metallic core of a largeish asteroid. This is based upon:
Answer:
This is based upon the fact that meteorites are generally believed to have originated as solid debris from Larger bodies like meteoroid or asteroids
Explanation:
Iron meteorites are interpreted as deriving from the cooled metallic core of a larger asteroid , because meteorites are generally believed to have originated as solid debris from Larger bodies like meteoroid or asteroids that are located outside the planet but found their way into our planet .
on what factor does speed of sound depend
Answer:
For sound waves to travel, there is a requirement of medium and density of the medium is considered to be one of the factors on which the speed of sound depends. When the medium is dense, the molecules in the medium are closely packed which means that the sound travels faster.
Explanation:
write the application of gravitational force
Answer:
Applications of Gravitational Force:
Gravity keeps your feet on the ground. Gravity holds the air down. Gravity makes the Earth roughly spherical. Gravity keeps the Moon (and all those artificial satellites) orbiting around the Earth. Gravity keeps the Earth orbiting around the Sun and the Sun orbiting around the galactic centre. Gravity creates the water pressure that runs hydroelectric turbines at the bottom of dams. Gravity brings the rain back down after it evaporates into the atmosphere.how much energy must be absorbed by 20.0 g of water to change its temperature from 95 degrees celsius to 125 degrees celsius
Answer:
I got 2508 J
Explanation:
q=mct
125-95
= 30 * 4.18 * 20
= 2508