21. A shot-putter moves his arm and the 7.0-kg shot : 2102102
21. A shot-putter moves his arm and the 7.0-kg shot through a distance of 1.0 m, giving the shot a velocity of 10 m/s from rest. Find the average force exerted on the shot during this time.
A. 175 N
B. 350 N
C. 525 N
D. 700 N
22. A baseball batter hits an incoming 40-m/s fastball. The ball leaves the bat at 50 m/s after a ball-on-bat contact time of 0.030 s. What is the force exerted on the 0.15-kg baseball?
A. 450 N
B. 250 N
C. 90 N
D. 50 N
23. In the terminology a 500-N block, the 500-N refers to the block's:
D. None of the above.
24. The statement by Newton that "for every action there is an opposite but equal reaction" is regarded as which of his laws of motion?
25. A thrown stone hits a window, but doesn't break it. Instead it reverses direction and ends up on the ground below the window. In this case, we know:
A. the force of the stone on the glass > the force of the glass on the stone.
B. the force of the stone on the glass = the force of the glass on the stone.
C. the force of the stone on the glass < the force of the glass on the stone.
D. the stone didn't slow down as it broke the glass.