Energy Work and Power

Question 1

Energy may be stored as kinetic, gravitational potential, chemical, elastic, nuclear, electrostatic and internal (thermal)

Question 2

Energy is transferred between stores by transfer of forces (Work Done), electrical currents (Electrical work done), heating, and by electromagnetic, sound and other waves

Question 3

Kinetic energy is known by the equation 1/2mv squared

Question 4

Gravitational Potential Energy is known by the equation G.P.E = mgh

Question 5

The principle of conservation of energy states that energy cannot be created or destroyed, only transferred. Should be able to understand Sankey diagrams.

Question 6

Mechanical or electrical work done is equal to the energy transferred. W=Fd=change in E

Question 7

Obtaining useful energy from chemical energy in fossil fuels involves burning the fuels to boil water, and using the steam to drive a turbine attached to a generator. Thus method in unrenewable and has a large environmental impact, but is readily available and reliable.

Question 8

Obtaining useful energy from chemical energy in biofuels involves burning the fuels to boil water, and using the steam to drive a turbine attached to a generator. This is a renewable, reliable, and environmentally friendly resource.

Question 9

To obtain energy from water, hydroelectric power stations involve the water driving a turbine attached to a generator. Tidal energy cannot be created also be obtained by driving a turbine with the tidal movement. While these are renewable resources, they impact the local environment.

Question 10

Energy from geothermal resources is obtained by heating up water in hit undergound pipes, and using the steam to drive a turbine attached to a generator. Renewable, reliable, and low impact, however low output.

Question 11

Nuclear fuels involves harnessing energy from nuclear fission. It is non renewable but readily available with a high output, however the is the risk of radioactive waste.

Question 12

Light from the sun is used in solar panels. This is renewable howver unreliable as only available on cloudy days. Very little environmental impact.

Question 13

Infrared and other waves from the sun produce wind energy, which we can harvest through turbines attached to generators. This is renewable yet unreliable and with a low output

Question 14

Radiation from the Sun is the main source of energy for all our energy resources except geothermal, nuclear and tidal

Question 16

Energy is being released from the Sun by nuclear fusion, and this is being investigated to see if nuclear fusion can produce large scale safe electricity.

Question 17

Efficiency is useful energy output/total energy input (x100 for a %)
Or
Useful power output/total energy input( x100 for a %)

Question 18

Power is work done per unit time and energy transferred per unit time
P=W/t
P=change in E/t