Topic 2 - Energy (GCSE Edexcel Combined Physics Retrieval Questions)

What is a closed system?

The set environment within which energy is transferred

What is the energy associated with movement?

Kinetic Energy

What type of energy is a longitudinal wave with a speed of 330m/s in air?

Sound Energy

What sort of energy is given off by fluorescent objects?

Light Energy

What type of energy is stored in stretched objects

Elastic Energy

What type of energy is found in the nuclei of atoms?

Nuclear Energy

What type of energy is found in objects raised off the ground?

Gravitational Potential Energy

What type of energy is given off by hot objects?

Thermal Energy

What type of energy is carried by electrons carrying a charge?

Electrical Energy

What type of energy is found in bonds between substances?

Chemical Energy

What is energy?

The ability to do work.

What is the unit of energy?

Joules (J)

What are the energy stores?

Chemical, kinetic, gravitational, elastic, thermal, magnetic, electrostatic and nuclear

How is energy transferred?

Mechanically, electrically, by heating, by radiation (sound and light)

What is the principle of conservation of energy?

Energy cannot be created or destroyed, only transferred.

What is a sankey diagram?

Scale diagrams which summarise all the energy transfers taking place in a process.

"In a closed system what will happen to the total energy?

There will be no net change in the total energy"

What do the widths of the arrows represent on a Sankey diagram?

The amount of energy

Give the equation linking work done, force and distance

Work done = force x distance

What is the unit of work done?

Joules (J)

What is the unit of force?

Newtons (N)

What is the unit of distance?

meters (m)

What is the relationship between energy transferred and work done?

Energy transferred = work done

Give the equation linking gravitational potential energy, mass, height and g.

GPE = mass x height x g

What is the unit of mass?

kilograms (kg)

Give the equation linking kinetic energy, mass and velocity

KE = 0.5 x mass x velocity²

What is the relationship between GPE and KE for a falling object?

GPE is transferred to KE

If a object is in freefall, what does it variables affect it's speed if there is no air resistance?

Gravity and Height

When energy is wasted, what happens?

It is dissipated into the surroundings.

Give the equation linking efficiency, useful energy output and total energy input.

Efficiency = (useful energy output/total energy input) x 100%

How can you reduce wasted energy?

Lubrication and thermal insulation

What is power?

The rate of energy transfer.

Give the equation linking power, energy and time

Power = energy/time

What is the unit of power?

Watts (W)

What is the unit of time?

seconds (s)

Give the equation linking power, work done and time

Power = work done/time

Does a good insulator have a high or low thermal conductivity?

Low thermal conductivity

What is meant by a non-renewable energy resource?

It cannot be replaced once it has been used

Name two harmful gases released when we burn fossil fuels

Carbon dioxide and sulphur dioxide

Why is carbon dioxide harmful?

It is a greenhouse gas and causes global warming

Why is sulphur dioxide harmful?

It causes acid rain

Why are coal particulates harmful?

Lung cancer and global dimming

Which non-renewable energy resource has the shortest start up time?

Gas

Which non-renewable energy resource has the shortest start up time?

Nuclear Power

What is an advantage of solar power?

No carbon dioxide released, reduces people's electricity bills if they have solar panels

What is a disadvantage of solar power?

Unreliable due to night and clouds, lots of space needed

What is an advantage of wind power?

No carbon dioxide released

What is a disadvantage of wind power?

Unreliable due to intermittent wind, noise and visual pollution

What is an advantage of tidal power?

Reliable, no use of land, no carbon dioxide released

What is a disadvantage of tidal power?

Only works with countries with a coastline, doesn't work well in bad weather

What is an advantage of hydroelectric power?

Quick start up time, reliable, no carbon dioxide released

What is a disadvantage of hydroelectric power?

Needs a lot of space, flood risks

What is an advantage of wave power?

No carbon dioxide released, no use of land

What is a disadvantage of wave power?

Doesn't work well in bad weather, dangerous to marine life

What is an advantage of geothermal power?

Reliable, very little carbon dioxide released

What is a disadvantage of geothermal power?

Needs a lot of access to water, drilling deep into ground could cause sink holes

What is an advantage of biofuel?

Fuel can be regrown, carbon neutral

What is a disadvantage of biofuel?

Food shortages, fuel groth takes up lots of space

What is an advantage of fossil fuels?

Reliable, quick start up time

What is a disadvantage of fossil fuels?

Releasing carbon dioxide which contributes to global warming, will run out in 50-100 years

What is an advantage of nuclear power?

Very high energy output per 1kg of fuel, no carbon dioxide released from

What is a disadvantage of nuclear power?

Dangerous waste which is expensive to store, risk of nuclear accidents

Once water is heated in a power station, what happens?

Steam turns a turbine, which powers a generator which generates electricity.