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neurologyYou need to know

• Energy can be stored in different ways, including chemical, kinetic, gravitational potential, elastic potential, thermal, electrostatic, magnetic, and nuclear energy stores.
• Energy can be transferred between stores by mechanical work, electrical work, heating, and radiation.
• When an object falls, energy is transferred from its gravitational potential energy store to its kinetic energy store.
• When a falling object hits the floor and does not bounce, energy in its kinetic energy store is transferred to the thermal energy stores of the object and the surroundings, and to the surroundings by sound waves.
• Work done is defined as the transfer of energy when a force moves an object over a distance, and `W = F \times s`, where `s` is the distance moved in the direction of the force.
• Work done on an object transfers energy to it, whereas work done by an object transfers energy away from it.
• Mechanical work against friction transfers energy to the thermal energy stores of the interacting objects and the surroundings.
• The kinetic energy of an object depends on its mass and the square of its speed, as shown by `KE = \frac{1}{2}mv^2`.
• The elastic potential energy of an object depends on how much it is stretched or compressed and its spring constant, as shown by `E = \frac{1}{2}ke^2`.
• The gravitational potential energy of an object depends on its mass, height, and the gravitational field strength, as shown by `GPE = mgh`.
• The gravitational potential energy store of an object increases when it is lifted and decreases when it is lowered.
• It is easier to lift an object on the Moon than on Earth because the Moon has a lower gravitational field strength.
• Specific heat capacity is the amount of energy required to raise the temperature of 1 kg of a substance by 1°C.
• Useful energy is transferred to produce the desired outcome, whereas wasted energy is transferred to undesired stores, often by heating or sound waves.
• Wasted energy is dissipated to the surroundings, usually as thermal energy, and becomes less useful.
• Energy is supplied to homes mainly as electricity and gas.
• Everyday electrical appliances receive energy electrically and transfer it to other stores, such as thermal or kinetic energy stores, or to the surroundings by light or sound waves.
• Power is the rate at which energy is transferred or work is done, as shown by `P = \frac{E}{t}`.
• The power of an electrical appliance is calculated using `P = VI`.

• Identify and describe the energy stores and transfer pathways in a given scenario.
• Analyse and describe the energy transfers that occur when an object falls and when it hits the ground without bouncing.
• State the definition of work done, and distinguish between energy transferred to an object by work done on it and energy transferred away by work done by it.
• Calculate the work done by a force using `W = F \times s`, where the distance is measured in the direction of the force.
• Explain, using examples, how mechanical work against friction transfers energy to the thermal energy stores of the interacting objects and the surroundings.
• Describe and explain how the mass and speed of an object affect its kinetic energy.
• Calculate the kinetic energy of an object using `KE = \frac{1}{2}mv^2`.
• Describe and explain how the spring constant and extension or compression of an object affect its elastic potential energy.
• Calculate the elastic potential energy stored in an object using `E = \frac{1}{2}ke^2`.
• Describe how the gravitational potential energy store of an object changes as it moves up or down.
• Calculate the change in gravitational potential energy using `GPE = mgh`.
• Explain, using the concept of gravitational field strength, why it is easier to lift an object on the Moon than on Earth.
• Define specific heat capacity and use it in calculations.
• Carry out a practical investigation to determine the specific heat capacity of a material, including accurate measurement and control of variables.
• Calculate the energy required to change the temperature of an object using `E = mc\Delta\theta`.
• Identify useful and wasted energy transfers in a range of devices and scenarios.
• Explain what happens to energy that is wasted and describe how it is dissipated.
• Describe how energy is supplied to homes and the main energy transfer pathways in domestic appliances.
• Select an appropriate electrical appliance for a specific application based on its energy transfer characteristics.
• Calculate the power of an electrical appliance using `P = \frac{E}{t}` and `P = VI`.