Enter your Name:   Enter your E-mail Address:  Be sure to write all your answers with the proper number of significant figures and to list the units that go with your answers! 01. State Newton's three laws of motion in your own words. 02. A Bicyclist is traveling at high speed and is not watching where he is going. His front tire catches in a sewer grating, causing the bike to stop almost instantly. This makes the rider fall off of the bike. Which way will the biker fall and why? 03. Two objects have different weights. The first is twice as heavy as the second. If they are each placed on the same surface, which will experience the greatest friction? How much greater will the frictional force be? 04. You find a measurement of 34 kg written in a laboratory notebook. What physical characteristic is this a measurement of? 05. From experience, we all know that you must push an object harder to get it moving than you do to keep it moving once it has already started. Using arguments at an atomic level, explain why this is the case. 06. A physicist is using tools that measure length in cm, mass in mg, and time in minutes. If the physicist measures a force and does not convert any units, what will the force unit be? 07. A parent asks a physics student to move a couch. The physics student, having just read about Newton's Third Law, has just learned that for every force applied, there is an equal and opposite force. He therefore reasons that when he pushes the couch, an equal and opposite force will cancel out his force, making it imposssible to move the couch. What is wrong with the student's reasoning? 08. A pole-vaulter vaults over a 10-foot high bar and lands on a large cushion. When the pole-vaulter hits the cushion, he exerts a force on it. What is the evidence of this force? What is the equal and opposite force demanded by Newton's Third Law, and what is the evidence of that force? 09. Assuming that there is no friction, how much force is necessary to accelerate a 152 gram object at 1.21 m/sec2? 10. An object has a mass of 34 slugs. What is its weight? 11. A rocket ship weighs 24,561 Newtons on earth. How much will it weigh on Jupiter? (The acceleration due to gravity on Jupiter is 23.2 m/sec2.) 12. If a rock has a mass of 44 slugs on Venus, how much will it weigh on earth? (The acceleration due to gravity on Venus is 28 ft/sec2.) 13. A person is pushing on a 567-pound statue. What frictional force must be overcome to get the statue moving ( = 0.32, = 0.20)? 14. A tractor pulls a 721-kg crate with a force of 3,123 Newtons. If the coefficients of friction are = 0.42, = 0.30, how fast will the crate accelerate, provided that it is already moving? 15. A mover pushes a 1,451-pound piano across a cement driveway ( = 0.42, = 0.24). Assuming that the mover has already gotten the piano moving, how much force must the mover push with in order to keep the piano moving at a constant velocity?