A simple pendulum is 8.00 m long. (a) What is the period of small oscillations for this pendulum if it is located in an elevator accelerating upward at 7.00 m/s2? s
(b) What is the period of small oscillations for this pendulum if it is located in an elevator accelerating downward at 7.00 m/s2? s
(c) What is the period of this pendulum if it is placed in a truck that is accelerating horizontally at 7.00 m/s2? s

1) when you rub your hands together quickly, the kinetic energy is converted to mechanical energy.2) thermal energy from the sun travels to earth as infrared waves.3) energy is transferred through the matter of space by electromagnetic waves. 4) when a match is burned, chemical potential energy is converted to thermal and radiant energy. 5) seismicwaves are caused by back and forth movement , or vibration, of an object. 6) mechanicalenergy in an engine changes thermal energy into kinetic energy to make a car move.

Where are the options ?

Answer(a)   the matererials that are in contact, the two materials and the nature of their surfaces/// (b)/// the force pushing the two surfaces together, pushing the surfaces together causes the more of the asperities to come together and increases the surface area in contact with each other