Transcript Momentum & impulse

Some ice falls off the top of a moving truck and hits the
windshield of a car. The effect is potentially more serious if
(a) the truck is moving in the opposite direction to the car
(b) the truck is moving in the same direction as the car
(c) It makes no difference whether the truck
is moving in the same direction or the
opposite direction to the car.
A constant force is exerted for a short time interval on a cart that
is initially at rest on an air track. This force gives the cart a
certain final speed. The same force is exerted for the same length
of time on another cart, also initially at rest, that has twice the
mass of the first one. The final speed of the heavier cart is
(a) one-fourth
(b) four times
(c) half
(d) double
(e) the same as that of the lighter cart.
A constant force is exerted on a cart that is initially at rest on an air
track. Friction between the cart and the track is negligible. The
force acts for a short time interval and gives the cart a certain final
speed. To reach the same final speed with a force that is only half
as big, the force must be exerted on the cart for a time interval
(a) four times as long as
(b) twice as long as
(c) equal to
(d) half as long as
(e) a quarter of that for the stronger force.
Consider two carts, of masses m and 2m, at rest on an air
track. If you push first one cart for 3 s, and then the other for
the same length of time, exerting equal force on each, the
momentum of the light cart is
(a) one-quarter the momentum of the heavy cart.
(b) one-half
(c) equal to
(d) twice
(e) four times
A 1-kg ball is dropped from a height of 5 m. When the ball
hits, how much force does it exert on the ground?
(a) 0.2 N
(b) 5 N
(c) 49 N
(d) 9.8 N
(e) impossible to determine
A cart moving at speed v collides with an identical stationary cart
on an air track, and the two stick together after the collision. What
is their velocity after colliding?
(a) v
(b) 0.5 v
(c) zero
(d) –0.5 v
(e) –v
A billiard ball of mass m is rolling across a table with the velocity
shown below, when it collides with a second ball of the same
mass.
1. What is the value of the total momentum in the x direction after
the collision?
2. What is the value of the total momentum in the y direction after
the collision?
(a) mv1 cos1  mv 2 cos2
(b) mv1 sin 1  mv 2 sin 2
(c) mv1 cos1  mv 2 cos2
(d) mv1 sin 1  mv2 sin 2
(e) zero