1. Calculate the kinetic energy of a football of mass 0.4kg moving with a speed of
20m/s.
2. Taking g = 9.8N/kg, calculate the potential energy gained by a 0.1kg mass raised
vertically by 1m.
3. A boulder of mass 4kg rolls over a cliff and reaches the beach below with a velocity
of 20m/s. Calculate
a) the kinetic energy of the boulder as it lands
b) the gravitational potential energy of the boulder when it was at the top of the cliff
c) the height of the cliff.
4. How much work is done when a mass of 3kg (g = 9.8 N/kg) is lifted vertically through
6m?
5. Describe how useful energy may be obtained, or electrical power generated, from:
(a) chemical energy stored in fossil fuels (b) chemical energy stored in biofuels (c)
hydroelectric resources (d) solar radiation (e) nuclear fuel (f) geothermal resources
(g) wind (h) tides (i) waves in the sea.
6. Define power and state its sI unit.
7. Define pressure and state its sI unit.
8. Describe how the height of a liquid column in a liquid barometer may be used to
determine the atmospheric pressure.
9. Describe, quantitatively, how the pressure beneath the surface of a liquid changes
with depth and density of the liquid.