General Physics 1 (PHY2048) QUIZ 2A Chapters 5-8 Last name: Pfannenstiel First name anner Date: 2/79/24 1. A tired worker pushes a heavy (100-kg) crate that is resting on a thick pile carpet. The coefficients of static and kinetic friction are 0.6 and 0.4, respectively. The worker pushes with a force of 500 N. The frictional force exerted by the surface is 1000 N A) B) 600 N C) 500 N D) 400 N E) 100 N 2. A block of wood is pulled by a velocity with a force of 20 N. 0.3. The force of friction is horizontal string across a rough surface at a constant The coefficient of kinetic friction between the surfaces is A) impossible to determine without knowing the mass of the block. B) impossible to determine without knowing the speed of the block. C) 0.3 N D) 6N E) 20 N 3. The kinetic energy of a car is 1.00 105 J. If the car's speed is increased by 20 percent, the kinetic energy of the car becomes A) 4.00 10 J B) 1.20 x 105 J C) 1.44 x 105 J D) 1.04 10$ J E) unknown; the answer depends on the mass of the car, which is not given 4. A constant force of 45 N directed at angle 0 to the horizontal pulls a crate of weight 100 N from one end of a room to another a distance of 4 m. Given that the vertical component of the pulling force is 12 N, calculate the work done by the force in moving the crate. A) 4.1 x 102 J B) 48.0 J C) 3.9 102 N/m D) 1.7 102 J E) 3.9 10 J