A closed system consists of a pendulum that is swinging back and forth. If the pendulum's gravitational potential
energy decreases, what else must happen to the energy of the
system?
O A. Its total mechanical energy must decrease.
O B. Its kinetic energy must decrease.
O C. Its kinetic energy must increase.
D. Its total mechanical energy must increase.

Amplitude is a measure of a waves a; speed b; distance c; energy d; frequency

Ateam of astronauts is on a mission to land on and explore a large asteroid. in addition to collecting samples and performing experiments, one of their tasks is to demonstrate the concept of the escape speed by throwing rocks straight up at various initial speeds. with what minimum initial speed vesc will the rocks need to be thrown in order for them never to "fall" back to the asteroid? assume that the asteroid is approximately spherical, with an average density p 3.84 x108 g/m3 and volume v 2.17 x 1012 m3 recall that the universal gravitational constant is g 6.67 x 10-11 n m2/kg2

In order to place a satellite into orbit, it requires enough fuel to supply the necessary mechanical energy. into what types of mechanical energy does the fuel get transformed?