a. Which vehicle experiences the greater force?
b. Which experiences the greater acceleration? Explain briefly.
33. Is it possible for me to wave my hand and keep the rest of my body perfectly still? Why or why not?
34. How does a rocket accelerate in space, where there is nothing to ‘push off’ against?
Answers (using g = 10 m/s2 ): 11. Zero; weight of the hammer minus the air resistance. 12. 2 forces 13. 1 force 14. No 15. The towel’s inertia resists the acceleration 16a. 100 N 16b. 100 N 17. 50 kg; 80 N 18. The rope will not break because his weight of 800 N is distributed between the two ropes. 19. Yes, because his weight of 800 N is greater than what the rope can hold. 22b. a = 0.71 m/s2 22c. v = 2.7 m/s 22d. 350 N 23a. 400 N 23b. 500 N 24a. 100,000 N 24b. 20 m/s2 25b. −1.1 m/s2 25c. 2.4 m 26b. 500 N www.ck12.org
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