(Draw the appropriate diagrams for each question, and using the concepts of gravity, force, work, energy, etc.)

1. Fan on a Lab Car

A small lab car (m = 200 g) has a fan affixed to the top of it that supplies the car with a constant force to the left. Make sure to show work and/or explain your reasoning.

a. Draw a free body diagram for the cart.

b. If the car is initially moving to the right, what is the direction of the acceleration of the car at the point farthest to the right it will travel (i.e., where it will change directions)?

c. Are any of the forces you identified in part A Newton's third pairs? If so, which forces are pairs, and how do you know? If not, why not?

2.Swinging

Salvatore is swinging on a swing set. The chains holding the swing are 5.00 m long and Salvatore is pulled back to an angle of 5 from vertical by his friend. How fast will Salvatore be moving at the lowest point in the swing?

3. Bicycling Down a Hill

Ji-Soo and her bicycle have a total mass of 60.0 kg. At the top of a hill, Ji-Soo's speed is 5 m/s and her speed doubles as she rides down the hill. The hill is 10.0 m high and 100 m long.

a. How much work is done on Ji-Soo and her bicycle by friction?

b. If it takes Ji-Soo 10.5 seconds to reach the bottom of the hill, how much power did she generate?

4. Box of Fruit

A grocer is working to unpack a truck full of produce. The grocer accidentally drops a 10.0 kg box of fruit on the ramp off the truck that is angled 10 below horizontal. The box of fruit accelerates down a ramp at 1.0 m/s². The coefficient of kinetic and static friction between the box and ramp is 0.25 and 0.36, respectively.

a. What is the magnitude of the normal force acting on the box of fruit?

b. What is the magnitude of the kinetic friction force acting on the box of fruit?

5. A 1,200 kg car is driving around a banked turn that is angle 12.0 above horizontal, as shown in the figure below. The car is traveling at a constant angular velocity of 12.0 rad/s around the track. The horizontal distance between the car and the center of the track is 12.0 m, as shown in the figure below. Assume that the track is slippery due to an oil leak. Calculate the centripetal force acting on the car.

Side View Top View Car 12.0 m 12.0 m 120 Car - - - - VTs,max = UsN fr = URN = -kAx