Mission WE3 Kinetic and Potential Energy
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A 5-kg object is moving with a speed of 4 m/s at a height of 2 m. The potential energy of the object is approximately ____ J.
The potential energy is the energy stored in an object due to its vertical position above (or below) the ground or some zero level. The amount of potential energy (PE) possessed by an object depends upon its mass (m) and its height (h). The formula for calculating the potential energy is
where g is the gravitational field strength (9.8 N/kg on Earth).
PE = m • g • h
where g is the gravitational field strength (9.8 N/kg on Earth).
This is a straightforward calculation of potential energy from mass and height. Of course the speed value which is stated has nothing to do with the potential energy calculation. To be approximate (and arrive at the answer more quickly), use the approximation that g is 10 N/kg.
