Arrange the steps in order to describe what happens to a gas when it cools.
tiles
the particles of gas move slower.
the gas changes to a liquid.
the gas loses thermal energy.
the space between the gas particles decreases.

Astone weighing 1.5 kilograms is resting on a rock at a height of 20 meters above the ground. the stone rolls down 10 meters and comes to rest on a patch of moss. the gravitational potential energy of the stone on the moss is joules.