1. The diaphragm of a speaker has a mass of 76.5 g and responds to a signal of frequency 3.20 kHz by moving back and forth with an amplitude of 1.80 10⁴ m at that frequency.

What is the maximum force acting on the diaphragm?

_______________ kN

2. A baby jumper consists of a cloth seat suspended by an elastic cord from the lintel of an open doorway. The unstretched length of the cord is 1.20 m, and the cord stretches by 0.198 m when a baby of mass 6.80 kg is placed into the seat. The mother then pulls the seat down by 7.90 cm and releases it.

What is the period of the motion?

________________ s

3. A bob of mass m is suspended from a string of length L, forming a pendulum. The period of this pendulum is 2.0 s. If the pendulum bob is replaced with one of mass 1/3m and the length of the pendulum is increased to 3.00L, what is the period of oscillation?

_______________ s