Q1. An air puck of mass 0.026 kg is tied to a string and authorized to revolve in a circle of radius 1.5 m on a frictionless horizontal surface. The other end of the string passes through a hole in the center of the surface, and a mass of 1.7 kg is tied to it, as shown. The suspended mass remains in equilibrium even as puck revolves on the surface. What is the magnitude of the force that maintains circular motion acting on puck?

Q2. A damped mass-spring system oscillates at 220 Hz. The time constant of the system is 2.0 s. At t = 0, amplitude of oscillation is 5.1 cm and the energy of the oscillating system is then 51 J.