Py 211 module 16 Problem 1 You are helping your friend move a new refrigerator into his kitchen. You apply a horizontal force of 265 N in the negative Wm try and move the 59 kg refrigerator. The coefficient of static friction is 0.73. A. How much static frictional force does the floor exert on the refrigerator? Give both magnitude (in N) and direction. B. What maximum force (in N} do you need to apply before the refrigerator starts to move? Problem 2 A block of mass m rests on a rough incline plane. Which of the following is the correct free-body diagram for this situation? Problem 3 In an exciting game, a baseball player manages to safely slide into second base. The mass of the baseball player is 77.7 kgand the coefficient of kinetic friction between the ground and the player is 0.52. A. Find the magnitude of the frictional force in newtons. B. It takes the player 1.7 s to come to rest. What was his initial velocity (in m/s)? Problem 4 A block of mass m1 = 36 kg on a horizontal surface is connected to a mass m2 = 22.0 kg that hangs vertically as shown in the figure below. The two blocks are connected by a string of negligible mass passing over a frictionless pulley. The coefficient of kinetic friction between m1 and the horizontal surface is 0.22. m m, A. What is the magnitude of the acceleration (in m/s2) of the hanging mass? B. Determine the magnitude of the tension (in N) in the cord above the hanging mass. Problem 5 A book of mass 7 kg rests on a plank. You tilt one end of the plank and slowly increase the angle of the tilt. The coefficient of static friction between the book and the plank is 0.46. What is the maximum angle of tilt for which the book will remain stationary and not slide down the plank? Problem 6 A contestant in a winter games event pushes a 32.0 kg block of ice across a frozen lake as shown in the figure below. The coefficient of static friction is 0.1 and the coefficient of kinetic friction is 0.03. (Assume 0 = 210.) A. Calculate the minimum force F (in N) he must exert to get the block moving. B. What is its acceleration (in m/s2) once it starts to move, if that force is maintained?Problem 7 To maintain a constant speed, the force provided by a car's engine must equal the drag force plus the force of friction of the road (the rolling resistance). The density of air g A. What are the drag forces in newtons at 79 km/h and 106 km/h for a Toyota Camry? (Drag area = 0.70 m2 and drag coefficient = 0.28.) B. What are the drag forces in newtons at 79 km/h and at 106 km/h for a Hummer H2? (Drag area = 2.44 rn2 and drag coefficient = 0.57.) Problem 8 A spherical raindrop 2.3 mm in diameter falls through a vertical distance of 4600 rn. Take the cross- sectional area of a raindrop = m2, drag coefficient = 0.45, density of water to be 1000 kg/rn3, and density of airto be 1.2 kg/m3. A, Calculate the speed a spherical raindrop would achieve falling from 4600 m in the absence of air drag. B. What would its speed be at the end 0f4600 m when there is air drag? {Note that the raindrop will reach terminal velocity after falling about 30 m.)