BIO How High Can We Jump?? The maximum height a typical human can jump from a crouched start is about 60 cm. By how much does the gravitational potential energy increase for a 72-kg person in such a jump? Where does this energy come from?
Solution 2E The expression for gravitational potential energy is given by E = mgh, where m is the mass of the body, g is acceleration due to gravity and h is the height of the body from ground. Given that, h = 60 cm = 0.6 m m = 72 kg g = 9.80 m/s 2 Therefore, the increase in gravitational potential energy is 2 E = 72 kg × 9.80 m/s × 0.6 m E = 423 J So, the approximate change in gravitational potential energy of the person is 423 J. Human body gets energy from the food that is consumed. Food calories are stored as fat in our muscles. When we jump a part of food energy is converted to kinetic energy and at the maximum height kinetic energy is transformed to potential energy.
