Lesson 9 hw

1) Can an object move along a curved path if no force acts on it? Defend your answer.

2) The diameter of the base of the bottom of a drinking cup is 5.0 cm.

The diameter of its mouth is 8.5 cm. The bath of the cup curves when you roll it on the top of a table.

Which end. the base or the mouth. rolls faster?

Part B

How much faster?

3) To tighten a bolt, you push with a force of 85 N at the end of a wrench handle

that is 0.35 m from the axis of the bolt

Part A

What torque are vou exerting?

Part B

if you move your hand inward to be on v 0.10 mm from the bolt

Ting the Torce that you should exert to achieve the same torque

Express your answer with the appropriate units

4) The rock and meterstick balance at the 25-cm mark, as shown in . The meterstick has a mass of 1.2 kg. What must be the mass of the rock? Express your answer with the appropriate units. 5) An ice puck of mass m revolves on an icy surface in a circle at speed v at the end of a horizontal string of length L as shown in figure. "The tension in the string is T. a) What is the equation of the centripetal force? b) Rearrange the equation to solve for mass. Express your answer in terms of the variables T, L, and v. c) Find the mass of the puck when the length of the string is 2.0 m, string tension is 18 N, and the tangential speed of the puck is 2.0 m/s. Express your answer with the appropriate units