Q1. The arrangement in the drawing shows a block (mass = 14.7 kg) that is held in position on a frictionless incline by the cord (length = 0.602 m). The mass per unit length of the cord is 1.24 e-2 kg/m, so the mass of the cord is negligible compared to the mass of block. The cord is being vibrated at a frequency of 167 Hz (vibration source not shown in the drawing). What is the smallest angle θ between 15.0 degree and 90.0 degree at which a standing wave exists on cord?

Q2. The area of the piston in the master cylinder is 1.75 cm2, and that of the piston in the brake cylinder is 6.40 cm2. The coefficient of friction between shoe and wheel drum is 0.50. If the wheel has a radius of 44 cm, find out the frictional torque about the axle when the force of 45 N is exerted on the brake pedal.