Question 29
A roller-coaster train of mass 2000 kg is stationary at top of the track. The train has gravitational potential energy of 3000 kJ. When released, it rolls down the track. When it reaches the bottom of the track, it has a gravitational potential energy of 2000 kJ and a speed of 20 m/s at the bottom of the track. [Formula for kinetic energy = ½ × mass × (speed)²] How much energy is lost in the form of heat and sound?