Question

1.3

You have a pendulum of mass m and length l. You pull it back so the string

makes a 10◦ angle with the vertical. What is the torque on the pendulum

immediately after you release it? What is it when the pendulum is hanging

straight down? Drawing a force diagram may be helpful.

1.4

Samwell and Sydney are trying to loosen a bolt on their car. Samwell can exert

a maximum force of 52 Newtons, and has a wrench that is 30 cm long. Sydney

can only exert a maximum force of 45 Newtons, and has a wrench that is 40 cm

long. How much torque do they exert on the bolt? Who has a a better chance

at getting the bolt loose?

1.5

You are attempting to launch your friend Jim into the air using a see-saw: Jim

stands on one end, and you will jump on the other, making him shoot up into

the air. Where, relative to the center, should Jim stand? Where on the see-

saw should you jump to maximize how high Jim goes? A drawing with arrows

indicating the positions is a sufficient answer.

Answer 1