For a roller coaster as shown in the figure, which one of the following is correct? A Potential energy at the mean position (point 3) is one-half of the potentials at points 2 and 4. B Kinetic energies at the two extreme positions (points 1 and 5) are equal but non-zero. C Kinetic energies at the two extreme positions (points 1 and 5) are equal and zero. D Potential energy at the mean position (point 3) is twice of the potential at point 2 or at point 4.

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 ?