<span>the gravational potential energy of anything on the ground is zero. When calculating potential energy you take height in meters and multiply it by the mass of the object in kilograms and the acceleration of gravity to get a new unit called Joules.
Any object at ground level has a potential energy of zero newtons becuase anything multiplied by zero is zero. An object with mass of 54 kg, 4 meters above the ground has a gravitatinal potential energy of 2116.8 Joules.</span>
A firecracker before been lit has potential energy in it. It is chemical potential energy which is due to the explosives in it.When it is lit, it gets converted into heat,light and kinetic energy.
Velocity is height , speed is an object being propelled by force
