Solve the final speed: 2 cars each with a mass of 2 kg are headed toward each other at 5 m/s, what would be the SPEED of each car after a perfect elastic collision?
5 m/s
20
A freight train rolls along a track with considerable momentum. If it rolls at the same speed but has twice as much mass, its momentum is
A) zero.
B) doubled.
C) quadrupled.
D) unchanged.
B) doubled.
15
It is correct to say that impulse is equal to
A) momentum.
B) the change in momentum it produces.
C) the force multiplied by the distance the force acts.
D) velocity multiplied by time.
B) the change in momentum it produces.
15
A rifle recoils while firing a bullet. The speed of the rifle's recoil is small because the
A) force against the rifle is smaller than against the bullet.
B) rifle has much more mass than the bullet.
B) rifle has much more mass than the bullet.
15
Two objects have the same size and shape, but one is much heavier than the other. When they are dropped simultaneously from a tower, they reach the ground at the same time, but the heavier one has a greater
momentum.
10
To catch a ball, a baseball player extends the hand forward before impact with the ball and then lets it ride backward in the direction of the ball's motion. Doing this reduces the force of impact on the player's hand principally because..
time of impact is increased.
15
When you jump you usually bend your knees upon reaching the ground. By doing this, you make the time of the impact about 10 times as great as for a stiff-legged landing. In this way the average force your body experiences would be...
10 x less
15
A bullet is fired from a gun. The speed of the bullet will be about the same as the speed of the recoiling gun if the mass of the bullet...
if the mass of the bullet equals the mass of the gun.
15
Padded dashboards in cars are safer in an accident than
non-padded ones because an occupant hitting the dash has...(relate to time)
