# Physics-Kinetic energy

81,313 results

### Physics kinetic energy

Okay the equation for kinetic energy is = 1/2mv^2 so how would i figure this out?? If a semi-truck decreases its speed from 10 m/s to 5 m/s, its new Kinetic Energy is: a)4 times its old Kinetic Energy b)2 times its old Kinetic Energy c)1/2 its old Kinetic Energy d)1/4 its old ...

### Physics

A 5.36 kg object falls freely (ignore air resistance), after being dropped from rest. Determine the initial kinetic energy, the final kinetic energy, and the change in kinetic energy for the following. (a) first meter of fall initial kinetic energy 0 J final kinetic energy ___...

### Physics

Two objects are mocing about so that their total momentum is zero. What can be said about their kinetic energy? Choose the most descriptive answer. a. the kinetic energy must be greater than zero b. the kinetic energy must be negative c. the kinetic energy must be equal to or ...

### PHYSICS

A hollow tube (I = MR2) rolls without slipping along the surface. The ratio of its translational kinetic energy to its rotational kinetic energy is a. 1 b. 2 c. 3 d. 1/2 e. 1/3 I say A becasue both add up to get the total kinetic energy.

### science(physics)

A 2kg stone is droped from the top of a 20m building a)what potential energy does it posses b)At what height does its potential energy become equal to its kinetic energy? c)what is its kinetic energy just before it hits the ground? d)With what velocity does it reach the ground...

### Physics

A rolling barrel with initial velocity 20 m/s encounters a hill 10m tall to slow it down 1. state where its angular speed is 0 2. state where its rotational kinetic energy will be 0 3. state where its translation kinetic energy will be 0 4. for each of the two flat surfaces ...

### Physical Science

Can someone please check these answers for me? Write T for True or F for False for each statement: 1.Kinetic energy is the energy of motion - T 2.Kinetic energy doesn't depend on an object's direction. - T 3.When an object stops moving, its kinetic energy is zero. - T 4.As the...

### physics

compute the kinetic energy of an 1800 lb automobile traveling at 30 mi/hr. how many times as great is the kinetic energy if the velocity is doubled? compute the kinetic energy, in erg and in joules, of a 2 gram bullet travelling at 500 m/sec.

### PHYSICS

Kinetic Energy and the Work/Energy Theorem: 1.) How much kinetic energy does a 700-gram baseball have that is travelling at 20 m/s? What would be the kinetic energy if you doubled the mass? What would be the kinetic energy if you doubled the velocity? 3.How much work must ...

### Science

which of the following is true about kinetic energy select all that apply A as an objects speed increases kinetic energy decreases B only moving objects have kinetic energy ••• C kinetic energy increases as an objects height increases D kinetic energy depends on an ...

### science

A ball sitting on the top of a table has potential energy but no kinetic energy. How do potential and kinetic energy change as the ball falls off the table to the floor? A. Its potential energy increases, and its kinetic energy decreases. B. Its potential energy decreases, and...

### science

A ball sitting on the top of a table has potential energy but no kinetic energy. How do potential and kinetic energy change as the ball falls off the table to the floor? A. Both its potential energy and its kinetic energy decrease. B. Both its potential energy and its kinetic ...

### science 8th grade

1. The thermal energy of an object is _____. (1 point) its potential energy its average kinetic energy its potential energy minus its kinetic energy its kinetic energy plus its potential energy Thanks, jessica :)

### physics-energy conservation

when you apply the brakes of a car its kinetic energy or energy of motion decreases. a)to what form of energy is the kinetic energy converted? b)where does the resulting energy end up? Do the brake drums on the wheels heat up? so does it convert into heat energy?and the ...

### Chem please help

An object A has half the mass and twice the velocity of object B. How are the kinetic energies of A and B related? A. The kinetic energy of B is 4 times that of A. B. The kinetic energy of B is twice that of A. C. The kinetic energy of A is the same as that of B. D. The ...

### physics

a bowling ball has a mass of 8kg. if it rolls down the alley, without slipping, at 7m/s, calculate a) the linear kinetic energy, b) the rotaional kinetic energy, c) the total kinetic engergy

### Physics

A 245 g particle is released from rest at point A inside a smooth hemispherical bowl of radius 35.0 cm, as shown in Figure 5-21. (a) Calculate the gravitational potential energy at A relative to B. 1 . (b) Calculate the particle's kinetic energy at B. 2 (c) Calculate the ...

### physics

jack measured that his racquet gives a squash ball 45.0J of kinetic energy when he hits it with a particilar shot.he also measures that it has 18.0J of kinetic energy after one bounce off the court wall. what percentage of its mechanical energy does the ball lose while it ...

### Physics

due to conservation of mass, potential energy should always equal to kinetic energy. one possible reason the calculation for kinetic energy might be less than potential energy is _

### physics

A. A particle is traveling without friction up and down hills and valleys. If its initial potential energy is 6 J and its initial kinetic energy is 78 J, what is its total energy, E? E: J B. If at a later point its potential energy is -14 J, what is its kinetic energy K at ...

### Chemistry

What change would occur in the kinetic energy of vapor if a container of vapor is placed at 0 Kelvin? A.The kinetic energy of gas particles will increase. B.The kinetic energy of gas particles will decrease. C.The kinetic energy of gas particles will remain unchanged. D.The ...

### physics

A particle is traveling without friction up and down hills and valleys. If its initial potential energy is 85 J and its initial kinetic energy is 83 J, what is its total energy, E? E: Correct: Your answer is correct. J B. If at a later point its potential energy is 131 J, what...

### Physics

A 1000kg space craft at 500m/s is on a collision course with a 400kg satellite travelling at 700m/s. Their paths are converging at a 45 degree angle. After the collision, they remain locked together. a) calculate their final speed b) calculate the quantity of non-kinetic ...

### Physics

A 1000kg space craft at 500m/s is on a collision course with a 400kg satellite travelling at 700m/s. Their paths are converging at a 45 degree angle. After the collision, they remain locked together. a) calculate their final speed b) calculate the quantity of non-kinetic ...

### physics help 3 please!!

A 2.0 kg cylinder (radius = 0.08 m, length = 0.50 m) is released from rest at the top of a ramp and allowed to roll without slipping. The ramp is 0.77 m high and 5.0 m long. (a) When the cylinder reaches the bottom of the ramp, what is its total kinetic energy? (b) What is its...

### physics

If there is just one force acting on an object, does its work necessarily result in an increase in kinetic energy? Explain. (Select all that apply.) 1.Yes, when a force does work on an object it always results in an increase in kinetic energy. 2.The work done by the force on ...

### physics

If there is just one force acting on an object, does its work necessarily result in an increase in kinetic energy? Explain. (Select all that apply.) 1.Yes, when a force does work on an object it always results in an increase in kinetic energy. 2.The work done by the force on ...

### Physics-Kinetic energy

Two 2.0 g bullets are fired with speeds of 40.0 m/s and 80.0 m/s, respectively. What are their kinetic energies? Which bullet has more kinetic energy? What is the ratio of their kinetic energies? A car has kinetic enery of 4.32* 10^5 when traveling at a speed of 23m/s. What is...

### physics

Which of the following is true about frictional forces? 1) They are stored as frictional potential energy. 2) They can decrease kinetic energy. 3) They produce heat potential energy. 4) They eventually convert to electromagnetic potential energy. 5) They can increase kinetic ...

### physics

A neutron in a reactor makes an elastic head-on collision with a nitrogen atom that is initially at rest. (The mass of the nitrogen nucleus is about 14 times that of the neutron.) (a) What fraction of the neutron's kinetic energy is transferred to the nitrogen nucleus? (b) If ...

### Physics

A single conservative force F(x) acts on a 1.6 kg particle that moves along an x axis. The potential energy U(x) associated with F(x) is given by U(x) = -2.9xe-x/3 where x is in meters. At x = 3.4 m the particle has a kinetic energy of 7.2 J. (a) What is the mechanical energy ...

### Physics- PLEASE HELP

A 10.0 kg cylinder rolls without slipping on a rough surface. At an instant when its center of gravity has a speed of 16.0 m/s, determine (a) the translational kinetic energy of its center of gravity.(b) the rotational kinetic energy about its center of gravity, and (c) its ...

### physics

A 2.10-g particle is released from rest at point A on the inside of a smooth hemispherical bowl of radius R = 28.0 cm. Calculate the following: (a) Its gravitational potential energy at A relative to J (b) Its kinetic energy at B. J (c) Its speed at B. m/s (d) Its potential ...

### Physics

A pitcher claims he can throw a 0.157 kg baseball with as much momentum as a 1.5 g bullet moving with a speed of 1.50 multiplied by 103 m/s. (a) What must the baseball's speed be if the pitcher's claim is valid? m/s (b) Which has greater kinetic energy, the ball or the bullet...

### physics

Question Part Submissions Used A 11.5-kg cylinder rolls without slipping on a rough surface. At an instant when its center of gravity has a speed of 10.9 m/s, determine the following. (a) the translational kinetic energy of its center of gravity J (b) the rotational kinetic ...

### Physics ~please help me!

1.) A car (m=1200 kg) moves form 2.0 m/s to 15.0 m/s in 100 m. a) What is the initial kinetic energy of the car? b) What is the final kinetic energy of the car? c) what is the net work applied to the car? d) what force is applied to the car? 2.) A simple pendelum is 1.5 m long...

### Physics

please check: Which of the following energy forms is associated with an object in motion? a. potential energy b. elastic potential energy c. nonmechanical energy d. kinetic energy i think its B Which of the following energy forms is associated with an object due to its ...

### PHYSICS helppppp

A 0.2 kilogram baseball is thrown vertically downwards towards to the same horizontal floor. The baseball possesses an initial velocity of 30 meters per second. The height is 10.00m. (A) Calculate the POTENTIAL GRAVITATIONAL ENERGY and KINETIC ENERGY of the baseball at the ...

### physics

A 2 kg rock is released from rest at a height of 29 m. Ignore air resistance and determine the kinetic energy, gravitational potential energy, and total mechanical energy at each of the following heights;20m 15m 9m * physics - bobpursley, Wednesday, November 17, 2010 at 9:32am...

### physics

A boulder flies through the air at 14.5 m/s with kinetic energy 310 J. What's its mass? What's the boulder's kinetic energy if its speed doubles? What's the boulder's kinetic energy if its speed is halved?

### Physics

When a skydiver jumps from a plane and achieves terminal speed. Which quantity remains constant? (a) Momentum (b) kinetic energy (c) potential energy (d) both a and b (e) both a and c I say kinetic energy, am i right?

### physics

A particle has a kinetic energy equal to its rest energy. (a) What is the speed of this particle? (b) If the kinetic energy of this particle is doubled, does its speed increase by more than, less than, or exactly a factor of 2? (c) Explain (d) Calculate the speed of a particle...

### physics

Show that the kinetic energy of two particles with mass m1 and m2 split into the energy of the centre of mass and the kinetic energy of relative motion.

### Physics

I need help with part b, c, and d please! A 45 g mass is attached to a massless spring and allowed to oscillate around an equilibrium according to: y(t) = 1.4 * sin( 4 * t ) where y is measured in meters and t in seconds...

### Science

Classify each of the following as examples of kinetic or potential energy. a) a car driving along a level road. b) an elastic band is stretched to twice its normal length c) a book is at rest on the top shelf of a bookcase d) a lightning bolt produces thunder that travels at ...

### physics

A 2.48-kg rock is released from rest at a height of 28.1 m. Ignore air resistance and determine (a) the kinetic energy at 28.1 m, (b) the gravitational potential energy at 28.1 m, (c) the total mechanical energy at 28.1 m, (d) the kinetic energy at 0 m, (e) the gravitational ...

### physics

A 2.48-kg rock is released from rest at a height of 28.1 m. Ignore air resistance and determine (a) the kinetic energy at 28.1 m, (b) the gravitational potential energy at 28.1 m, (c) the total mechanical energy at 28.1 m, (d) the kinetic energy at 0 m, (e) the gravitational ...

### physics

A 3.56-kg rock is released from rest at a height of 15.2 m. Ignore air resistance and determine (a) the kinetic energy at 15.2 m, (b) the gravitational potential energy at 15.2 m, (c) the total mechanical energy at 15.2 m, (d) the kinetic energy at 0 m, (e) the gravitational ...

### physics

A bowling ball of mass 7.45 kg is rolling at 2.56 m/s along a level surface. (a) Calculate the ball's translational kinetic energy. J (b) Calculate the ball's rotational kinetic energy. J (c) Calculate the ball's total kinetic energy. J (d) How much work would have to be done ...

### Physics

A bowling ball of mass 7.45 kg is rolling at 2.56 m/s along a level surface. (a) Calculate the ball's translational kinetic energy. J (b) Calculate the ball's rotational kinetic energy. J (c) Calculate the ball's total kinetic energy. J (d) How much work would have to be done ...

### physics

A bowling ball of mass 7.45 kg is rolling at 2.56 m/s along a level surface. (a) Calculate the ball's translational kinetic energy. J (b) Calculate the ball's rotational kinetic energy. J (c) Calculate the ball's total kinetic energy. J (d) How much work would have to be done ...

### Physics

A physics textbook is launched up a rough incline with a kinetic energy of 200 joules. When the book comes momentarily to rest near the top of the incline, it has only gained 180 joules of gravitational potential energy. About how much kinetic energy will it have when it ...

### Physics

Determine the ratio of the relativistic kinetic energy to the nonrelativistic kinetic energy (1/2mv2) when a particle has a speed of (a) 2.12 x 10-3c. and (b) 0.959c.

### Physics

A cricket ball hits the ground with kinetic energy K at an angle 30* with the vertical. What will be its kinetic energy at the highest point?

### Physics

If an object starts at the origin (of a graph) moving to the right with a kinetic energy of 45.5 J, how much kinetic energy does it have at x = 3.0 m?

### Physics

Determine the ratio of the relativistic kinetic energy to the nonrelativistic kinetic energy (1/2mv2) when a particle has a speed of (a) 2.60 × 10-3c. and (b) 0.972c

### physics

How do i find this? A shooting star is a meteor that burns up when it reaches Earth's atmosphere. Many of these meteoroids are quite small. Calculate the kinetic energy of a meteoroid of mass 6.0 g moving at a speed of 45 km/s and compare it to the kinetic energy of a 1400-kg ...

### physics

A motorcycle, an automobile and a bus are all traveling at the same speed. Which has the least kinetic energy? The greatest kinetic energy?

### physics

suppose an automobile has a kinetic energy of 2900J. when it moves with 3 times the speed, what will be its kinetic energy? answer in the units of joules

### physics

A 4 kg projectile has 1400 J of kinetic energy when it leaves the ground. If it has 120 J of kinetic energy at its highest point, how high did it travel?

### physics

How much kinetic energy is gained by an electron that is allowed to move freely through a potential difference of 2.5 × 10^4 V? -- U=qV =(1.6*10^-19)(2.5*10^4) =4*10^-15 I'm not sure what other formulas i can use, or how to relate potential energy to kinetic energy because ...

### Physics

If a 1000-kg car was moving at 30 m/s, what would be its kinetic energy expressed in the unusual (for kinetic energy) units of calories? (1 cal = 4.186 J)

### physics

In the reaction U gives Th + He 6.88*10-13 J energy are released as the kinetic energies of the products. If the ratios of the masses Th to He is 2.4:4 find the kinetic energy of the alpha particle

### Physics

In the reaction U gives Th + He 6.88*10-13 J energy are released as the kinetic energies of the products. If the ratios of the masses Th to He is 234:4 find the kinetic energy of the alpha particle

### Physics

I need help with b... I found that k=.750880 for part a but I can't figure out what y would be to get potential energy. A 52 g mass is attached to a massless spring and allowed to oscillate around an equilibrium according to: y(t) = 0.8 * sin( 3.8 * t ) where y is measured in ...

### college physics

Explain each of the following questions. ( a) Can an object– Earth system have kinetic energy and not gravitational potential energy? ( b) Can it have gravitational potential energy and not kinetic energy? ( c) Can it have both types of energy at the same moment? ( d) Can it...

### physics

Friction converts kinetic energy to a. mechanical energy b. potential energy c. nonmechanical energy d. total energy i don't think its B,..

### physics kinetic energy

a) if a particle's speed decreases by a factor of four, by what factor does its kinetic energy change? b) particle A has three times the mass and twice the kinetic energy of particle B. What is the speed ratio VA / VB?

### physics

determine the kinetic energy of falling by an average of one degree of freedom of the nitrogen molecule at temperature T = 1000 K, as well as the kinetic energy of rotational motion.

### Physics

A thin-walled sphere rolls along the floor. What is the ratio of its translational kinetic energy to its rotational kinetic energy through its center of mass?

### Physics

A thin-walled sphere rolls along the floor. What is the ratio of its translational kinetic energy to its rotational kinetic energy through its center of mass?

### physics

Explain each of the following questions. ( a) Can an object– Earth system have kinetic energy and not gravitational potential energy? ( b) Can it have gravitational potential energy and not kinetic energy? ( c) Can it have both types of energy at the same moment? ( d) Can it...

### Physics

in a compressed spring, energy is in the form of (a) kinetic energy (b) potential energy (c) chemical energy (d) sound energy

### Integrated Physics and Chemistry

The internal energy of a material is determined by.. A)its temperature B)the kinetic energy of its molecules C)the potential energy of its molecules D)the combined amount of kinetic and potential energy of its molecules

### Physics

A projectile leaves the ground at an angle of 60degree to the horizontal.it initial kinetic energy is E. Neglecting air resistance, it kinetic energy at the highest point of the motion is

### Physics 1 Collision Math

Mass A, 2.0kg , is moving with an initial velocity of 7 m/s in the +x-direction, and it collides with mass B,4.0kg , initially moving in the +x-direction. After the collision, the two objects stick together and move as one. What is the change in kinetic energy of the system as...

### physics

A 20.0-kg model plane flies horizontally at a constant speed of 12.2 m/s. (a) Calculate its kinetic energy. . J (b) The plane goes into a dive and levels off 20.0 m closer to Earth. How much potential energy does it lose during the dive? Assume no additional drag. J (c) How ...

### Physics

A 5 kg ball is initially at rest at the top of a hill 10m high. If it rolls down the hill (converting all of its potential energy to kinetic energy,) what is the maximum kinetic energy it could have at the bottom of the hill? -I am not sure what formula to use?

### physics

a 2 kg object moving at 5 m/s enters a surface with the coefficient of kinetic friction is .1 and is brought to a full stop. If the cart moved 12.8 m calculate: a) the net work done on the object over the 12.8 m distance (I got 6.4j, but it's probably wrong) b) change in ...

### AP physics

A 1.60-g bullet, moving at 542 m/s, strikes a 0.249-kg piece of wood at rest on a frictionless table. The bullet sticks in the wood, and the combined mass moves slowly down the table. (a) Find the speed of the combination after the collision. m/s (b) Find the kinetic energy of...

### Physics Help!!

Suppose the kinetic energy of an object moving is 15 J and the potential energy is 25 J at some point in time. Then I measure the potential energy some time later and find it to be 10 J. What is the new kinetic energy?

### physics

Is it impossible to lose all of the kinetic energy in a collision? Or, does a ball which bounces several times before eventually coming to rest show how kinetic energy can completely disappear?

### Physics help

A solid cylinder rolls along the floor. What is the ratio of it's translational kinetic energy to its rotational kinetic energy about an axis parallel to its length and through its center of mass?

### PHYSICS HELP PLEASE!!!

A block of mass 2.62 kg is kept at rest as it compresses a horizontal massless spring(k = 141 N=m) by 15.3 cm. As the block is released, it travels 0.627 m on a rough hori- zontal surface before stopping. The acceleration of gravity is 9.8 m/s2 :Calculate the coe±cient of ...

### Physics

A sledder has 800 J of potential energy and 200 J of kinetic energy at one point on a steep hill. How much kinetic energy will the sledder have at the bottom of the hill? (Assume negligible air resistance and friction.)

### physics

I need help with this problem so please help me. 1. A certain photoelectric surface has a threshold frequency of 6.2*10^14 Hz. A. How much kinetic energy is required to produce an electron emission? B. if the surface is illuminated with light that has a frequency 7.1*10^14 Hz...

### physics

A car has a flywheel ( a diks of R=0.2m and uniformly distributed mass M=100kg) that can convert 25% of the rotational kinetic energy into translational kinetic energy. The mass of the car is 1000kg ( including flywheel). Suppose the car is at rest, and the flywheel has a ...

### Science (energy)

1. What similarities do nuclear energy and chemical energy share? Choose all that apply. A. Both are types of kinetic energy. B. Both are types of potential energy. [CORRECT!] C. Both involve magnetic energy. D. Both involve stored energy. [CORRECT!] 2. A student is trying to ...

### hellllp physics

A solid cylinder rolls along the floor. What is the ratio of it's translational kinetic energy to its rotational kinetic energy about an axis parallel to its length and through its center of mass?

### Physics

A hula Hoop (I=1/2MR^2) rolls without sliding along the floor. The ratio of its translational kinetic energy to its rotational kinetic energy (about an axis through its center of mass) is: A. 1 B. 2 C. 3 D. 1/2

### Physics (Potential & Kinetic energy)

A 2.0 kg rock falls from a height of 25 m to a point 20 m above the ground. a) how much potential energy does it lose? b) How much kinetic energy does it gain? Thanks.

### physics

In most situations, frictional forces tend to reduce the kinetic energy of an object. However, frictional forces can sometimes increase an object's kinetic energy. Describe a few situations in which friction causes an increase in kinetic energy.

### physics

A canon of mass 1100kg fires a cannonball of mass 6.2kg at a speed of 190ms-1. a) Calculate the initial recoil speed of the cannon. b)The purpose of the firing the canon is to transfer chemical energy of the explosive into kinetic energy of the cannon ball, but the cannon is ...

### Physics

How much kinetic energy does a 1 kg ball have if it has a velocity of 10 m/s? a. 100 J. b. 50 J. c. 10 J. d. 5 J. A ping pong ball and a golf ball move with the same kinetic energy. Which is moving fastest? (golf balls are heavier than ping pong balls). a. The ping pong ball ...

### physics

A block is initially sliding along a horizontal surface with 24.6 J of kinetic energy. Friction causes the block’s speed to be halved in a distance of 3.20 m. a) What is the kinetic energy of the block after traveling the 3.20 m? b) What is the magnitude of the kinetic ...

### Physics

A solid disk rolls along the floor with a constant linear speed v. (a) Find the fraction of its total kinetic energy that is in the form of rotational kinetic energy about the center of the ball. Krot/Ktotal = ?

### Physics Classical Mechanics

The figure below shows the experimental setup to study the collision between two carts. In the experiment cart A rolls to the right on the level track, away from the motion sensor at the left end of the track. Cart B is initially at rest. The mass of cart A is equal to the ...

### physics

A 3.00 g lead bullet traveling at 640 m/s strikes a target, converting its kinetic energy into thermal energy. It's initial temperature is 40.0°C. (a)Find the available kinetic energy of the bullet.(J) (b)Find the heat required to melt the bullet.(J)

### physics

A 3.00 g lead bullet traveling at 640 m/s strikes a target, converting its kinetic energy into thermal energy. It's initial temperature is 40.0°C. Find the available kinetic energy of the bullet. Find the heat required to melt the bullet.