physics
posted by Elisa .
A ball of mass 0.120 kg is dropped from rest from a height of 1.25 m. It rebounds from the floor to reach a height of 0.600 m. What impulse was given to the ball by the floor?

physics 
Damon
Impulse is change of momentum, integral of F dt
What you need to know is the speed of the ball down when it hits the floor, call that U (negative down), and the speed of the ball as it rebounds up, call that V (positive up)
then the impulse is m (V  U)
Those two speeds can be gotten from potential and kinetic energy relations.
the potential energy at 1.25 meters (mgh) is the kinetic energy at the floor (.5 m U^2)
so
9.8 * 1.25 = .5 U^2 (the mass on both sides cancels)
U^2 = 24.5
U = 4.95 (remember negative because down)
same deal for V but h in this case is .6 meters
9.8*.6 = .5 V^2
V = +3.43
V  U = 3.43  (4.95) = 8.38 m/s
That is the total change in velocity. Multiply by the mass to get the impulse or change in momentum
.120 * 8.38 = 1.01 kg m/s
U = 
physics 
drwls
I thought I'd answered this already, but my answer seems to have disappeared. Please read Damon's response and ignore the nonsense posted by John.

physicsghlk 
ghl
lghjkl
Respond to this Question
Similar Questions

Physics
A ball of mass 0.15kg is dropped from rest at a height of 1.25m. it rebounds from the floor to reach a height of 0.960n. what impulse is given to the ball from the floor? 
PHYSICS
A ball of mass 0.150kg is dropped from a height of 1.25m. It rebounds from the floor to reach a height of 0.960m. What impulse was given to the ball by the floor? 
physics
1. A centrifuge in a medical laboratory rotates at an angular speed of 3650 rev/min. When switched off, it rotates through 50.0 revolutions before coming to rest. Find the constant angular acceleration of the centrifuge. 2. A ball … 
momemtum ?
A ball of mass 0.150 kg is dropped from rest to a height of 0.125 m. It rebounds from the floor to reach a height of 0.960m. What impulse was given by the floor? 
physics 111
A ball of mass 0.120 kg is dropped from rest from a height of 1.25 m. It rebounds from the floor to reach a height of 0.600 m. What impulse was given to the ball by the floor? 
physics
A ball of mass 0.120 kg is dropped from rest from a height of 1.25 m. It rebounds from the floor to reach a height of 0.600 m. What impulse was given to the ball by the floor? 
Physics
A rubber ball of mass 41.5 g is dropped from a height of 1.75 m onto a floor. The velocity of the ball is reversed by the collision with the floor, and the ball rebounds to a height of 1.55 m. What impulse was applied to the ball during … 
physics
A rubber ball of mass 43.5 g is dropped from a height of 2.05 m onto a floor. The velocity of the ball is reversed by the collision with the floor, and the ball rebounds to a height of 1.55 m. What impulse was applied to the ball during … 
Physics
After a 0.200kg rubber ball is dropped from a height of 1.95 m, it bounces off a concrete floor and rebounds to a height of 1.45 m. (a) Determine the magnitude and direction of the impulse delivered to the ball by the floor. (b) Estimate … 
Physics
After a 0.200kg rubber ball is dropped from a height of 1.95 m, it bounces off a concrete floor and rebounds to a height of 1.45 m. (a) Determine the magnitude and direction of the impulse delivered to the ball by the floor. (b) Estimate …