Physics Practice Test
Chapter 8 Rotational Motion
DIRECTIONS: Answer all problems by showing work, being neat, using proper scientific notation, proper significant digits, proper units, and boxing all answers. POINTS WILL BE DEDUCTED!!!!!! For all short answer questions, make sure the answer is most correct and most complete.
1. A steel beam with a weight of 523N is 7.00m long. How much force would be required to lift one end of the beam off the floor if you are lifting 45cm from the end?
2. A 6.23m pipe is bent towards the ground with a torque of 15.9N by a giant gingerbread man with a mass of 24.31kg. At what angle did the confection hanging on the pipe apply the force?
3. A bridge 55m long has supports that are 4m in from each side. If the bridge has a mass of 6 .00 x 105kg and a truck with a mass of 3.53 x 104kg is parked 15m from the right side of the bridge and a crate with a mass 0f 750.0Kg sits 5.00m from the other side of the bridge, find the force exerted by each support so the truck does not plummet into the fiery stream of lava below
4. A rock troll pushes tangentially on a small hand-driven merry-go-round and is able to accelerate it from rest to 23.5rpm in 12.5s. Assume the merry-go-round is a uniform disk of radius 3.5m and has a mass of 626kg, and a child 17kg sits on the edge and another child 35kg sits 1.5m from the center. What force is required at the edge?
5. Calculate the moment of inertia of a bicycle wheel with a 24.6cm diameter if the rim and tire have a mass of 2.70kg.
SHORT ANSWER QUESTIONS:
1. Why do tightrope walkers carry a long, narrow beam?
2. Explain whether or not a small force can ever exert a greater torque than a larger force.
3. If an odometer is designed for a 27inch wheel but is placed on a bike with a 24-inch wheel, what conflicts if any would occur?
t = Fdsinq F1 d1 = F2 d2 St = t1 + t2 + ....
t = Ia a = v/r a =w2 - w1 /Dt