Question

15) A golf ball of mass 0.045 kg is hit off a tee at a speed of 45 m/s. The golf club was in contact with the ball for 3 ms (3 x 10's). Determine, in N, the average force exerted on the golf ball by the golf club a) 367 b) 675 c) 294 d) 579 Answer 16) Two railroad cars, each of mass 6650 kg and traveling 30 m/s toward each other, collide head-on and come to rest. Determine, in J, the amount of thermal energy produced in this collision a) 6 x 10 b) 2 x 10 c) 1 x 10 d) 8 x 10 Answer 17) Determine the work, in J, required to stop a 1500-kg car traveling at 30 m/s. (hint: use the work-energy theorem). a) 2.4 x 10 b) 8.2 x 10 c) 1.7 x 10 d) 6.8 x 10

Answer 1

15) By Newton's second law

force = rate of change of impulse

F = dp/dt

= mv/t

= 0.045*45 / 3*10^-3

= 675 N

so option b) is the correct answer