Answer;
85 joules
Explanation;
- From conservation of energy, the kinetic energy at take off equals the potential energy at the top of the jump.
- Potential energy = kinetic energy
- Potential energy = mgh , where m is the mass, h is the vertical height and g is the gravitational acceleration.
Therefore; energy = 7.2 × 9.8 × 1.2
= 84.672 Joules
= 85 joules
Thus, the kinetic energy is 85 joules.