11. Lonnie pitches a baseball of mass 0.20 kg. The : 2102134
11. Lonnie pitches a baseball of mass 0.20 kg. The ball arrives at home plate with a speed of 40 m/s and is batted straight back to Lonnie with a return speed of 60 m/s. If the bat is in contact with the ball for 0.050 s, what is the impulse experienced by the ball?
A. 360 N?s
B. 20 N?s
C. 400 N?s
D. 9.0 N?s
12. A ball with original momentum +4.0 kg?m/s hits a wall and bounces straight back without losing any kinetic energy. The change in momentum of the ball is:
B. -4.0 kg?m/s.
C. 8.0 kg?m/s.
D. -8.0 kg?m/s.
13. If a glass of water is on a table with a piece of paper under it, it is relatively easy to pull the paper out without disturbing the glass very much if the pull is done very quickly. This is because, with a quick pull:
A. the force on the glass will be less.
B. the momentum of the paper will be greater.
C. the time for the pull will be less.
D. the coefficient of kinetic friction will be less.
14. A car wash nozzle directs a steady stream of water at 1.5 kg/s, with a speed of 30 m/s, against a car window. What force does the water exert on the glass? Assume the water does not splash back.
A. 11 N
B. 45 N
C. 110 N
D. 440 N
15. The units of impulse are equivalent to:
A. those of energy.
D. those of force.