A ball of mass 500g is dropped from rest 2m above the ground. When it reaches the ground it is travelling at 5m/s. How much energy has been dissipated?
Initial energy (Gravitational Potential): E = mgh = 0.5 x 9.81 x 2 = 9.81J Final energy (Kinetic): E = mv2/2 = (0.5 x 52)/2 = 6.25J Energy lost = 9.81 - 6.25 = 3.56J
GB
Related Physics GCSE answers
All answers ▸Can you explain the difference between distance and displacement
Why does your hair stand on end when you touch a Van de Graaff generator?
An electric heater has a power of 1000W. It is connected to mains electricity (230V). The heater is equipped with an Earth wire. a) Calculate the current in the heater. b) Explain the role of the earth wire as a safety feature.
When a toothbrush is charging, p.d. across the primary coil is 230 V, p.d. across the secondary coil is 7.2 V. The primary coil in the charging base has 575 turns of wire on its coil. Find the number of turns on the secondary coil inside the toothbrush.