State the relation between the joule and kilocalories.

The image shows a pendulum in simple harmonic motion the pendulum starts at a and swing to e

Why is the energy that results from a roller coaster's position at the top of a hill referred to as potential energy?

The experiment done in lab is repeated, using a ball that has unknown mass m. you plot your data in the form of f 2 versus m/l, with f in rev/s, m in kg, and l in m. your data falls close to a straight line that has slope 3.19 m/(kg · s2). use g = 9.80 m/s2 and calculate the mass m of the ball.