Friday

April 18, 2014

April 18, 2014

Number of results: 117,400

**physics**

A ball attached to the end of a string is whirled on a horizontal circle at constant speed. Consider the linear momentum, total energy, and kinetic energy of the ball throughout its motion. Which of the following statements is true? Both linear momentum and kinetic energy are...
*Wednesday, January 6, 2010 at 11:01pm by hilary*

**College Physics II**

I heard you the first time. De Broglie wavelength is h/(momentum) h is Planck's cnstant Use the Kinetic Energy of the electron (E) to get the momentum. Momentum = sqrt(2E*m) The energy E will have to be in Joules. I trust you know how to make that conversion.
*Thursday, November 25, 2010 at 11:59am by drwls*

**modern physics - relativity**

A) You can find the velocity by cmputing the total energy and momentum. From: E = gamma m c^2 and P = gamma m v it follows that p/E = v/c^2 The total energy is: E + m0 c^2 The total momentum is the momentum of the photon, which is E/c. The total energy and momentum are ...
*Tuesday, June 7, 2011 at 3:24pm by Count Iblis*

**physics # 3**

3. In a perfectly inelastic collision which of the following is conserved, (give the most accurate answer). a.) Linear momentum b.) Kinetic energy c.) Linear momentum d.) Total mechanical energy, (KE +PE) e.) Heat energy
*Tuesday, August 7, 2007 at 11:44pm by gomez*

**Physics**

You drop an egg from rest with no air resistance. As it falls, a. only its momentum is conserved. b. only its kinetic energy is conserved. c. both its momentum and its mechanical energy are conserved. d. its mechanical energy is conserved, but its momentum is not conserved
*Saturday, March 5, 2011 at 6:25pm by Joe *

**Physics Momentum**

1. Momentum = m1V1 + m2V2=-1*5 + 1*5=0. 2. Momentum = m1V1 + m2V2 =20000+40000 = 60,000. 3. a. Energy doubles. b. 4 times. 4. Momentum = m*V = 4.5. 0.015*V = 4.5 V = 300 m/s.
*Wednesday, February 20, 2013 at 5:54pm by Henry*

**physics**

12. Which of the following statements is correct for a particle moving in a horizontal circle with constant angular velocity? A. The linear momentum is constant but the kinetic energy varies. B. The kinetic energy is constant but the linear momentum varies. C. Both kinetic ...
*Friday, November 1, 2013 at 2:23pm by shanza*

**physics (special relativity)**

Gamma rays of sufficient energy can create a positron and an electron, if the photon energy exceed 2 m c^2. This can only happen in the presence of another mass , which is needed to allow both energy and momentum to be conserved. Sone of the original photon momentum has to be ...
*Wednesday, June 8, 2011 at 2:44pm by drwls*

**physics**

i would choose the second option..both total energy and linear momentum are constant. Is this correct? tot. energy because kinetic energy is same since speed is the same and potential energy same since height stays the same. I'm not sure about linear momentum.. could someone ...
*Wednesday, January 6, 2010 at 11:01pm by hilary*

**Physics**

There is a force on it in the direction of motion. Therefore its kinetic energy increases. However its total mechanical energy including the gravitational potential energy is conserved. Meanwhile net force causes a rate of change of momentum, called acceleration when the mass ...
*Saturday, March 5, 2011 at 6:25pm by Damon*

**physics**

Determine for each of the following statements whether it is always true or can be false. In a perfectly inelastic collision, the kinetic energy is conserved. Kinetic energy is conserved in an elastic collision. Two objects of different masses but moving at the same velocity ...
*Friday, March 2, 2012 at 1:06pm by Katie*

**physics**

1. (avg. force)*(stopping distance) = (initial kinetic energy) = (1/2) M V^2 Solve for the initial force. The statement says that the work done frictionally heating the wood equals the in initial kinetic energy. 2. Impulse = -(intial momentum) = -M V 3. Change in momentum = -(...
*Tuesday, March 25, 2008 at 1:44am by drwls*

**Physics**

The sliding distance can be used to compute the kinetic energy of the joined cars. (friction force)*X = Kinetic energy at the beginning of skid. From the KE and masses, get the initial momentum of the joined cars. Once you have the momentum of the joined cars, you know that it...
*Thursday, October 20, 2011 at 11:30pm by drwls*

**Physics**

I have never know what a perfectly inelastic collision is. I do know what an inelastic collision is: Energy is NOT conserved. Ask your teacher this question, see if they know. Momentum applies: Now on this statement, conservation ofm momentum applies momentum before=momentum ...
*Saturday, December 11, 2010 at 1:02pm by bobpursley*

**Physics**

Use conservation of momentum Initial momentum: The momentum of inertia of the objects the students is m*r^2 (3.0 + 3.4*1^2 + 3.4*1^2)*wi = (3.0 + 3.4*.45^2 + 3.4*.45^2)*wf where wi = 0.75 is the initial angular momentum, and wf is the final angular momentum. Solve for wf b) ...
*Tuesday, November 27, 2012 at 10:59pm by Jennifer*

**Physics**

A hydrogen atom is in its third excited state (n=4). Using Bohr theory of the atom calculate (a) the radius of the orbit, (b) the linear momentum of the electron, (c) the angular momentum of the electron (d) the kinetic energy (e) the potential energy, and (f) the total energy...
*Saturday, April 28, 2012 at 3:27am by Chi*

**physics**

YOu have two equation, momentum, and energy. Use the momentum to find the velocity of one in terms of the other. Then substitute that found velocity in to the energy equation, and grind it out.
*Monday, January 10, 2011 at 10:10pm by bobpursley*

**Physics**

you have to use both conservation of momentum and energy. Start with conservation of momentum, solve for one of the ball's velocity in terms of all the other variables, then substitute that into the conservation of energy. The algebra is substantial, so be prepared.
*Tuesday, August 9, 2011 at 11:49pm by bobpursley*

**Physics**

a) momentum = mass * velocity Compute the velocity from the height it falls. Look up the formula for that or use conservation of energy. b) Impulse = momentum c) work done compressing carpet (F*X) = initial kinetic energy d) Same approach as (c) I will be happy to critique ...
*Wednesday, November 7, 2007 at 1:02pm by drwls*

**Physics**

(a) Photon energy = h*c/L Electron energy = (1/2)(momentum)^2/m = (1/2)*(h/L)^2*(1/m) Energy ratio (photon/electron) = 2*m*(hc/L)/(h/L)^2 = 2 m L c /h = ? m is the electron mass and L is the wavelength. h is Planck's constant. This assumes the de Broglie relation between ...
*Sunday, August 15, 2010 at 8:06am by drwls*

**Physics**

Find the linear momentum and kinetic energy of a bullet of mass 4.80e-2 kg moving at a speed of 320 m/s. I found the linear momentum to be 15.36 by doing m*v but I can't figure out the kinetic energy.
*Sunday, October 16, 2011 at 5:46pm by Kellie*

**Physics.**

What is the transfer mechanism of energy, momentum, and angular momentum?
*Sunday, November 27, 2011 at 1:12am by Kristin*

**physics**

To conserve both momentum and energy, the first ball stops and the second one continues with the total energy. In part 2, momentum is conserved but the motion continues with twice the mass. m g (.29)(1-cos 25) = .5 m v^2 solve for v then conservation of momentum at bottom (m+m...
*Friday, March 2, 2012 at 1:12pm by Damon*

**physics**

What you want is the total kinetic energy of BOTH of the skaters after she pushes him. Because they are on skates, and total momentum is conserved, she scquires the same momentum as her brother, but in the opposite direction. Her own velocity will be 68*3.7/45 = 5.59 m/s after...
*Monday, September 29, 2008 at 1:51am by drwls*

**PHYSICS**

example of inelastic collision, where momentum before = momentum after, and simply calculate the difference in energy then!
*Saturday, December 7, 2013 at 2:28am by enjoy*

**physics**

In a fully random distribution, we can determine the most probable state from what two quantities? Answer a. The number of particles and the net momentum. b. The number of particles and the total energy. c. The net momentum and the total energy. d. the total potential and the ...
*Friday, October 15, 2010 at 5:49pm by jim*

**physics**

The mass of a photon is zero; yet it has momentum. The momentum (as well as th energy) depends upon the frequency, which you have not provided.
*Saturday, May 9, 2009 at 7:29am by drwls*

**physics**

There is a relationship between momentum and energy KE = 1/2mv^2 p = mv m = p/v KE = 1/2 (p/v)v^2 KE = 1/2 pv From wiki answers The relation between kinetic energy is proportional to the square of velocity. Momentum is directly proportional to velocity. If the momentum of an ...
*Saturday, October 19, 2013 at 8:01am by Sarah*

**Physics 30**

Momentum is conserved in all collisions, but energy is another matter. KEnergy is conserved in elastic collisions, but not inelastic. Total energy, as including heat, friction, etc is always conserved, but I am not certain that is the point to this question. I would stick to ...
*Sunday, March 8, 2009 at 4:49pm by bobpursley*

**physics**

The momentum of the bullet equals the momentum of the block/bullet after impact. the energy of the block/bullet converts to potential energy in rising to the height. So work backwards, and solve for velocity of the bullet.
*Tuesday, March 4, 2008 at 11:59am by bobpursley*

**momentum**

Photons in general carry momentum so any electromagnetic wave has momentum associated with it despite its lick of rest mass in the classical sense. If a photon hits something, it moves it. E = energy of photon = m c^2 = h f where c is velocity of light and h is plank constant ...
*Tuesday, June 2, 2009 at 3:12pm by Damon*

**Physics - drwls?**

A 2000 kg truck traveling north at 38 km/hr turns east and accelerates to 55 km/hr. What is the change in the truck's kinetic energy? What is the magnitude of the change in the linear momentum of the truck? What is the direction of the change in linear momentum of the truck? (...
*Monday, March 19, 2007 at 11:51pm by winterWX*

**Physics**

Work backwards, because you cannot solve it forwards since there are two unknowns. (a) Start with the energy transferred to the compressed spring. The block transfers energy to the spring, that's why it compresses. Ek = Ee mv^2 = kx^2 (halves cancel) v = sqrt[(kx^2)/m] v = ....
*Tuesday, October 16, 2012 at 4:16pm by Richmond*

**physics**

A gun is fired vertically into a 1.55 kg block of wood at rest directly above it. If the bullet has a mass of 21.0 g and a speed of 190 m/s, how high will the block rise into the air after the bullet becomes embedded in it? i don't even know where to begin... would it have ...
*Tuesday, October 31, 2006 at 10:43pm by Haley*

**physics**

Which of the following statements is true for an inelastic collision? A. Both momentum and kinetic energy are conserved. B. Momentum is conserved, but kinetic energy is not conserved. C. Kinetic energy is conserved, but momentum is not conserved. D. The amount of momentum lost...
*Saturday, March 5, 2011 at 6:20pm by Joe *

**Physics**

Which of the following statements is true for an elastic collision? A. Both momentum and kinetic energy are conserved. B. Momentum is conserved, but kinetic energy is not conserved. C. Kinetic energy is conserved, but momentum is not conserved. D. The amount of momentum lost ...
*Saturday, March 5, 2011 at 6:20pm by Joe *

**Physics**

A bullet with a mass of 55 grams moving with a speed of 100 m/s slams into and wedges in a 1.9 kilogram block of wood supported by a string initially at rest. Which one, conservation of energy or conservation of momentum, can be applied to this situation? Why? I think it's ...
*Thursday, October 14, 2010 at 12:34am by Fred*

**Physics**

That's correct. Try to think about why angular momentum is conserved and why kinetic energy is not conserved. You can also consider a similar problem where the cord is not pulled but instead it is wrapping itself around a stick. What happens to angular momentum and kinetic ...
*Thursday, June 25, 2009 at 11:59pm by Count Iblis*

**physics**

In this situation, the balls exchange speeds and reverse direction. That keeps botht ehe kinetic energy and the linear momentum the same. V1(final) = 3 m/s V2(final) = 2 m/s You set up the momentum and kinetic energy equations and solve them, and you would get this result. It ...
*Sunday, March 20, 2011 at 2:45pm by drwls*

**Physics! - PLEASE HELP**

a) use conservation of energy. b) use conservation of momentum as the source for initial combined velocity, then conservation of energy to transform that KE to height. c. use conservation of momentum.
*Friday, August 26, 2011 at 10:36am by bobpursley*

**physics**

Ok, what is the change in momentum. Since the momentum parallel to the wall is the same, it does not change. So the momentum perpendicular (along the normal) is changed, it actually reverses, so one knows the change there, twice the initial momentum. Momentum normal=mvcos55.1 ...
*Tuesday, October 7, 2008 at 5:31pm by bobpursley*

**Physics**

energy in spring=1/2 kx^2 compute that. Intiial velocity of block/bullet combo: = 1/2 (M+m)V=energy in spring, solve for V Now, using the conservation of momentum momentumbullet=momentum(block+bullet) mVb=(m+M)V solve for Vb
*Sunday, November 11, 2012 at 11:01am by bobpursley*

**physics**

(a) For the electron, E = 3.2*10^-18 J momentum = sqrt(2m*E) = 2.41*10^-24 kg m/s wavelength = h/(momentum) = 2.74*10^-10 m For the photon, the energy is the same but wavelength = h*c/(Energy) = 6.2*10^-8 m (b) Use the formulas E(photon) = h*c/(wavelength) E(electron) = (...
*Tuesday, April 5, 2011 at 6:21am by drwls*

**Physics (MOMENTUM)**

Ball B. Momentum = m*V. Ek = 0.5m*V^2. Ball A: Momentum = (m/2)*2V = m*V. Ek = 0.5m*V^2 a. Their momentum is equal. b. Their kinetic energy is equal.
*Thursday, May 2, 2013 at 10:12pm by Henry *

**chemistry**

oh dear. u probably didnt understand the question. after u got the energy for N-N bond. U have to calculate lambda wavelength that too de broglie's. 0.5mv squared is the kinetic energy of the electron. So convert half mv squared to energy momentum equation. that should get u ...
*Saturday, June 1, 2013 at 8:15am by picha lite*

**chemistry**

oh dear. u probably didnt understand the question. after u got the energy for N-N bond. U have to calculate lambda wavelength that too de broglie's. 0.5mv squared is the kinetic energy of the electron. So convert half mv squared to energy momentum equation. that should get u ...
*Saturday, June 1, 2013 at 8:13am by picha lite*

**physics**

When a cannon fires a cannonball, the cannon will recoil backward because the a) energy of the cannonball and the cannon is conserved b) momentum of the cannonball and cannon is conserved c)energy of the cannon is greater than the energy of the cannonball d) momentum of the ...
*Wednesday, October 24, 2007 at 3:16pm by Tammy*

**physics**

the speed of the fastest pitched baseball was 45 m/s, and the ball's mass was 145 g. (a) What was the magnitude of the momentum of this ball, and how many joules of kinetic energy did it have? (b) How fast would a 57 gram ball have to travel to have the same amount of (i) ...
*Wednesday, October 28, 2009 at 4:59pm by sarah*

**physics**

(a): (minimum snow depth)*(maximum survivable force) = kinetic energy at impact = (1/2) M V^2 e (b) Impulse = momentum change = momentum at impact = M V
*Monday, July 7, 2008 at 7:45pm by drwls*

**Physics D**

The momentum in each direction is conserved. angle=arctan(momentum N/momentum E) velocity= (momnetum N + Momentum E)/total mass
*Monday, February 3, 2014 at 7:33pm by bobpursley*

**physics**

There are many parts to this question, and several different physics equations are needed to do the parts. I suggest you review how the De Broglie wavelength is related to momentum and Plank's constant, h. That will tell you the momentum, m V. Use the momentum and the electron...
*Monday, June 9, 2008 at 10:06pm by drwls*

**Physics -Spring Momentum**

energy= 1/2 k x^2 change in stored energy= 1/2 (50)(1/.08^2-1/.11^2)
*Friday, October 1, 2010 at 2:35pm by bobpursley*

**Energy and momentum Physics**

The vector sum of the momenta of the two cars before collision equals the momentum of the combined cars after collision. By solving the momentum conservation equations for two perpendicular axes, you can solve for both final speed and angle. We will happily critique your work...
*Thursday, February 3, 2011 at 9:36pm by drwls*

**Physics**

A 1200 kg car is moving on the freeway at 65 mph. (A) find the magnitude of its momentum and its kinetic energy in SI units. (b) if a 2400 kg SUV has the same speed asthe 1200 kg car, how much momentum and kinetic energy does it have?
*Monday, June 22, 2009 at 2:06pm by Sarah*

**physics**

A skater spinning with angular speed of 1.5 rad/s draws in her outstretched arms thereby reducing her moment of inertia by a factor a 3. a) Find her final angular speed. b)What is the ratio of her final angular momentum to her initial angular momentum? c) Determine the ratio ...
*Thursday, December 2, 2010 at 8:07pm by Kevin*

**chemistry**

question 1) oh dear. u probably didnt understand the question. after u got the energy for N-N bond. U have to calculate lambda wavelength that too de broglie's. 0.5mv squared is the kinetic energy of the electron. So convert half mv squared to energy momentum equation. that ...
*Sunday, June 2, 2013 at 11:41pm by picha lite*

**physics**

A cart of mass 340 g moving on a frictionless linear air track at an initial speed of 1.2 m/s undergoes an elastic collision with an initially stationary cart of unknown mass. After the collision the first cart continues in its original direction at .66m/s. a) what is the mass...
*Sunday, March 4, 2007 at 9:28am by Chris*

**physics**

Hints: when they shorten the rope, there is no external moment on he system so the angular momentum CAN NOT change. Get the new (higher)speeds from conservation of angular momentum. they did work shortening the rope so the energy goes up the work done equals the change in ...
*Saturday, December 1, 2012 at 8:47pm by Damon*

**physics**

write down in terms of the mass m and the velocity v of the body, expressions for i) momentum ii) the kinetic energy use your answer to (b) to help calculate the mass and the velocity of the ball momentum is mass*velocity Kinetic energy is 1/2 mass*velocity squared.
*Monday, October 16, 2006 at 11:28am by Kim*

**physics-help please........**

The momentum and the kinetic energy of particle A is eight times and nine times the momentum and the kinetic energy of particle B, respectively. What is the ratio of the mass of particle A to that of particle B?
*Sunday, October 30, 2011 at 12:03am by lost*

**physics**

Let a force of 1500 Newtons act through a distance of 200 meters on a 1500 kg car which starts from rest. a. What is the work done? b. What is the final velocity? c. What is the car's momentum? d. What is the car's change in momentum? e. What is the car's Kinetic Energy? f. ...
*Monday, November 14, 2011 at 8:46pm by Ryan*

**physics**

(a) Use conservation of momentum. The mechanical energy converted by the girl equals the increase in the combined kinetic energy of both
*Tuesday, February 23, 2010 at 7:24pm by drwls*

**Physics please explain**

In the quantum mechanical picture of the hydrogen atom, the orbital angular momentum of the electron may be zero in any of the possible energy states. For which energy state must the orbital angular momentum be zero? n = 1 n = 2 n = 3 n = 4 Give your reasoning. I am not sure ...
*Friday, December 14, 2007 at 1:33am by Mary*

**physics**

From the sliding distance and coefficients of friction, you can calculate the initial kinetic energy and momentum of piece L. From the fact that the total momentum must remain zero, you can conclude that the momenta of the two pieces are equal and opposite. Having solved for ...
*Wednesday, July 21, 2010 at 1:28pm by drwls*

**Physics ang. momentum**

The kinetic energy can increase because of muscular work done going into the tuck position. Remember that I * w remains constant. Angular momentum conservation is not violated. If the momen t of inertia I decreases by a factor of 3.5,then the angular frequency w increases by a...
*Monday, December 7, 2009 at 12:29am by drwls*

**Physics**

A satellite of mass m is in Keplerian orbit around a parent body of mass M >>m. The satellite has total energy E and angular momentum l, where angular momentum is measured about the parent body and the zero of potential energy is at infinity. Detnermine the semimajor ...
*Tuesday, May 10, 2011 at 3:58pm by Carole*

**Physics**

A satellite of mass m is in Keplerian orbit around a parent body of mass M >>m. The satellite has total energy E and angular momentum l, where angular momentum is measured about the parent body and the zero of potential energy is at infinity. Detnermine the semimajor ...
*Tuesday, May 10, 2011 at 5:08pm by Ferdinand*

**Physics**

A satellite of mass m is in Keplerian orbit around a parent body of mass M >>m. The satellite has total energy E and angular momentum l, where angular momentum is measured about the parent body and the zero of potential energy is at infinity. Detnermine the semimajor ...
*Tuesday, May 10, 2011 at 9:16pm by Carole*

**physics**

initial momentum = .005 v momentum after impact = .005 v = 1.5 V so V = .005 v/1.5 = .00333 v kinetic energy after impact = (1/2)(1.5)V^2 = 8.32*10^-6 v^2 final potential energy = mgh=1.5*9.81*.05 = 8.32*10^-6 v^2 so v^2 = 88467 v=297 m/s
*Sunday, August 25, 2013 at 2:51am by Damon*

**Physics Work and Energy, Momentum**

Let g be the acceleration due to gravity at the surface of a planet of radius R. Which of the following is a dimensionally correct formula for the minimum kinetic energy K that a projectile of mass m must have at the planet's surface if the projectile is to escape from the ...
*Sunday, May 13, 2007 at 4:35pm by Kelly*

**Physics: Collison/Momentum Problem**

conservation of energy. energy before= energy after 15*5^2+10*1^2=15*3^2+10*v^2 V^2= 1.5*25+1-1.5*9 v= 5m/s check the math.
*Wednesday, January 25, 2012 at 8:03pm by bobpursley*

**Physics**

two objects collide when sliding on a fricitonless horizontal surface. Which quantity is conserved during their collision? a) velocity b) momentum of both objects c)energy d) momentum of each object isn't c) or b) correct? I really think it's c)
*Wednesday, November 14, 2007 at 3:00pm by Andrea*

**physics**

First find the momentum of the block and embedded bullet right after the collision from conservation of energy: (1/2) m v^2 = m g h note m cancels h = 10 cm = .1 meter solve above for v m = 1.5 + .012 kg now momentum before = momentum after .012 Vbullet + 0 Vmass = 1.512 v so ...
*Monday, June 28, 2010 at 7:44pm by Damon*

**Physics**

What is the stored energy in the spring at max compression? What Veloicity does that equal on the block/bullet system. Waht momentum is that? Then, finally that momentum is the mometnum of the bullet...solve for bullet speed.
*Friday, December 10, 2010 at 2:23pm by bobpursley*

**special relativity **

The total energy of a system is given by: E = gamma m c^2 The total momentum is: p = gamma m v The ratio p/E is thus: p/E = v/c^2 So, if we know the energy and momentum of a system, we know the velocity. For the given system, the energy is: E = E1 + m2 c^2 The momentum is p = ...
*Tuesday, June 7, 2011 at 12:46pm by Count Iblis*

**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?
*Saturday, April 4, 2009 at 2:39pm by James*

**Physics**

+x to the right initial momentum = 3*4 - 8*1.5 = 0 so final momentum = 0 so final velocity = 0 energy is all gone Initial Ke = (1/2)(3)(16) + (1/2)(8)(2.25)
*Tuesday, January 1, 2013 at 10:22am by Damon*

**physics**

You write that: "(A)fter the collision, both ball(s) move at 30 degree and 15 degree from horizontal. " Which is it? Why use the word "both" if they leave at different angles? This is an exercise in momentum and kinetic energy conservation. Since there are only two unknowns, ...
*Wednesday, April 6, 2011 at 6:06am by drwls*

**Physics 30**

Momentum and angular momentum (which you may not have studied) are conserved in all collision. Kinetic energy is only conserved in special cases (like billiards) but is often approximately conserved. Total energy is conserved, but some may end up as internal inergy (heat; ...
*Wednesday, February 25, 2009 at 7:14pm by drwls*

**physics**

The momentum is conserved. Therefore the final momentum has E and S as before. Momentum E=56*2.8 momentum S=4.4*77 Use these to get the angle arctanTheta=MomentumS/momentumE where theta is the angle S of E.
*Thursday, October 16, 2008 at 7:59pm by bobpursley*

**Physics - momentum**

Hints: Conservation of momentum dictates that the components of momentum in the two (or any) orthogonal directions (x and y) should sum to zero, very much like forces in equilibrium. You can resolve the momentum of the two known pieces into the x- and y-directions and sum them...
*Sunday, June 24, 2012 at 5:18pm by MathMate*

**physics**

please check my answers what are the SI units for momentum? kg*m/s which of the following is not involved in hitting a tennis ball? a. kinetic energy b. chemical potential energy c. gravitational potential energy d. elastic potential energy i picked B How much power is ...
*Monday, February 16, 2009 at 8:35pm by y912f*

**Science**

We are studying energy my questions What happens to the momentum of a car when it comes to a stop? The momentum is transfered to the Earth. Momentum is always conserved. What happens to the momentum of a car when it comes to a stop?
*Tuesday, January 9, 2007 at 5:35pm by Mae*

**Physics**

Object A has mass mA = 9 kg and initial momentum A,i = < 19, -7, 0 > kg · m/s, just before it strikes object B, which has mass mB = 12 kg. Just before the collision object B has initial momentum B,i = < 5, 6, 0 > kg · m/s. Consider a system consisting of both ...
*Sunday, November 21, 2010 at 8:56pm by What does this even mean!?*

**Physics Momentum**

1) Two 1 kg balls move away from each other, one traveling 5 m/s to the right, the other 5 m/s to the left. What is the magnitude of the total momentum of the system? 2) Two 1000 kg cars drive east; the first moving at 20 m/s, the second at 40 m/s. What is the magnitude of the...
*Wednesday, February 20, 2013 at 5:54pm by Isis*

**Physics**

Lots of algebra here. Write the momentum equations in x and y directions, momentum has to be conserved in each direction. Once you find the velocity of the two girls, you can find the KE of each. Energy is probably not conserved.
*Sunday, October 7, 2012 at 8:35pm by bobpursley*

**physics conservation of momentum**

yeah i kno how to calculate those 2. i got 5 and -5... so is momentum conserved? because change in momentum would be 5 - (-5) = 10 but some ppl are telling me momentum is conserved because they are the same values.
*Saturday, November 8, 2008 at 9:46pm by rachel*

**PHYSICS**

1. Add the two impulses. 2. Apply the law of conservation of total momentum 3. The impulse equals the momentum change. Changing the direction of motion changes the sign 4. Subtract the final momentum from the initial momentum. Make sure you get the sign right on the final ...
*Thursday, December 4, 2008 at 10:30pm by drwls*

**Physics**

B: form conseravtion of momentum, which yields the angular velocities of 7 rad/sec that you used. D follows from conservation of energy. The work done equals the increase in kinetic energy.
*Thursday, June 25, 2009 at 11:59pm by Count Iblis*

**Physics**

The velocities are switched in this equal-mass elastic case. Object 1: 0 Object 2: 4.33 m/s It is obvious from inspection that both total momentum and kineticenergy are conserved. This can be proven with simultaneous momentum and energy equations, and I recommend that you try ...
*Thursday, November 8, 2007 at 3:10pm by drwls*

**physics**

work & energy homework problems: please help me =] my teacher is bad a teaching how to do stuff =/ 1)A 5.000kg plastic ball moves with a velocity of 10.00 m/s x. It collides with a second plastic ball of mass of 10.00kg at rest. The collision is completely elastic. find: a)the...
*Sunday, December 16, 2007 at 7:28pm by alissa*

**physics**

What is it you are failing to understand. Your subject listed is broad. angular motion angular momentum moments of inertia translation parallel axis theorem conservation of momentum conservation of energy coordinate systems, rotational
*Monday, October 6, 2008 at 12:24pm by bobpursley*

**PHYSICS**

1. Use conservation of momentum. Let the initial direction of X be considered positive. 20 - 12 = -2 + (momentum of Y) Momentum of Y = 10 N*s 2. Momentum of Force*t = 20i + 70j (N*s) is added to the body Initial momentum = 5i -10j Final momentum = 25i + 60 j Divide than by the...
*Friday, May 24, 2013 at 10:45am by drwls*

**physics**

(a) What is the frequency of a photon whose energy is 3.5 times the rest energy of an electron? (b) What would be the linear momentum of the photon?
*Friday, April 27, 2012 at 3:16pm by joe*

**Physics**

Use conservation of momentum. Total momentum (m v) will remain zero. Her momentum and the stone's momentum will be equal, but in opposite directions. The woman's mass is 770/9.81 = 78.5 kg 78.5*V = 2.6*35 Solve for V
*Friday, December 11, 2009 at 3:27am by drwls*

**Physics**

the correct equation is this: (.06)(225) = (5)(v) - (.06)(75) momentum is conserved. total momentum is equal to the momentum of the block minus the momentum of the bullet. you subtract because the two objects move in opposite directions.
*Saturday, October 27, 2012 at 8:49pm by Ricky*

**Physics**

IT is much to complicated to work out here. worke it this way: conservation of momentum in x direction conservation of momentum in y direction conservation of energy. That should give you all you need.
*Friday, October 23, 2009 at 11:19pm by bobpursley*

**Physics**

if KE is lost, energy was not conserved. So, momentum is not conserved. The missing energy is lost as heat. It's still present in the system, but the moving bodies no longer account for all the energy in the system.
*Friday, August 16, 2013 at 10:43pm by Steve*

**physics**

The sum of the momenta of the three pieces must equal the original momentum, 14*220 = 3080 kg m/s in the x direction. There is zero iniital momentum in the y direction. Write equations for the x and y components of total momentum with the component of the third part as the two...
*Tuesday, March 29, 2011 at 11:35pm by drwls*

**physics**

Use the potential energy and momentum. mommentum = mass times velocity So 2kg x 60m/s Take that answer and set it equal to the formula for potential energy. This works because when the rocks velocity is zero all the energy will be converted from kinetic energy to potential ...
*Saturday, March 23, 2013 at 10:02pm by Jared*

Pages: **1** | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | Next>>