This preview shows pages 1–2. Sign up to view the full content.
This preview has intentionally blurred sections. Sign up to view the full version.View Full Document
Unformatted text preview: Physics Honors Test: Chapter 4 FORM 1 DO NOT WRITE ON THIS TEST. REPORT ALL ANSWERS TO 3 SIGNIFICANT FIGURES . VECTOR ANSWERS MUST HAVE MAGNITUDE AND DIRECTION . USE SCIENTIFIC NOTATION WHEN APPROPRIATE t x v = t v a = at v v o f + = ax v v o f 2 2 2 + = 2 2 1 at t v x o + = 2 2 1 at t v x f- = ( 29 o f avg v v v + = 2 1 t v x avg = a F m = N s fs F F N k fk F F = g = 9.8 m/s 2 [D] A car with a mass of 1100 kg is being pulled by a tow truck. The tow truck pulls the car to the north with a constant 1200 N force, while a friction force pushes the car towards the south. Starting from rest, the truck pulls the car 60 meters toward the north in 25 seconds. 1) What is the magnitude of the friction force acting on the car? A horizontal 100-N force is applied to a 20-kg box that is initially at rest on the floor. The coefficient of static friction between the box and the floor is 0.40, and the coefficient of kinetic friction between the box and the floor is 0.35. 2) What is the magnitude of the force exerted by the ground on the box? A box slides at a constant rate of 4.0 m/s down an incline that makes a 40 angle with the horizontal. 3) What is the coefficient of kinetic friction? A 100-kg athlete is performing a vertical leap to test his leg strength. He leaves the ground at 3.20 m/s, zooms upward to some maximum altitude, and then returns to the ground. As he lands, he bends his legs and crouches down, so that he moves 30 cm downward as he comes to a stop. 4) What average force did the athletes legs exert on the ground as he landed? A 25-kg mass and a 15-kg mass are suspended from either side of a pulley by a massless rope, as shown at right. The pulley is massless and frictionless. The masses are released from rest. 5) What is the tension in the rope after the masses are released? A person exerts an upward force of 60 N to hold a backpack. This is the action force. 6) a) Describe the magnitude and direction of the reaction force. Be specific. b) Upon what object does the reaction force act? Be specific. c) What object exerts the reaction force? Be specific. A heavy box rests on the bed of a flatbed truck. When the truck accelerates, the crate remains where it is on the truck....
View Full Document
This note was uploaded on 08/29/2010 for the course PHYS 38234 taught by Professor Ramesh during the Spring '09 term at University of California, Berkeley.
- Spring '09