Exercise 5.33 You are lowering two boxes, one on top of the other down the ramp
ID: 3161804 • Letter: E
Question
Exercise 5.33 You are lowering two boxes, one on top of the other down the ramp shown in the figure (Figure 1) by pulling on a rope parallel to the surface of the ramp. Both boxes move together at a constant speed of 10.0 cm/s The coefficient of kinetic friction between the ramp and the lower box is 0.457, and the coefficient of static friction between the two boxes is 0.764. Part A What force do you need to exert to accomplish this? Submit My Answers Give Up Part B What is the magnitude of the friction force on the upper box? Submit My Answers Give UpExplanation / Answer
5.53
part A)
angular speed , w = 38.3 rev/min
w = 4.01 rad/s
part A) let the tension in the string is T
total weight , W = 269 + 810
W = 1079 N = 110.1 Kg
let the tension in the horizontal wire is T1
tension in the inclined wire is T2
balancing the vertical forces
T2 * cos(40) - 1079 = 0
T2 = 1408 N
the tension in the horizontal cable is 1408 N
balancing the horizontal forces
1408 * sin(40) + T1 = 110.1 * 4.01^2 * 7.50
solving for T1
T1 = 12373 N
the tension in the horizontal tension is 12373 N