The thermal energy of an object depends on
its temperature and mass
. The higher the temperature of a substance, the more thermal energy it has. For the same temperature, a substance with a higher mass will also have more thermal energy.
Which 2 factors affect the amount of energy an appliance transfers?
The kinetic energy of the hands moving around
. The sound energy of the ticking noise. The greater the amount of the supplied electrical energy that the appliance transfers to useful energy stores, the more efficient the device will be.
What two factors determine the amount of energy transferred by an electric oven?
- Temperature difference. The greater the difference in temperature between the two ends of the bar, the greater the rate of thermal energy transfer, so more heat is transferred. …
- Cross-sectional area. …
- Length (distance heat must travel). …
- Time.
What affects rate of energy transfer?
The rate at which an object transfers energy by heating depends on: the
surface area, volume and material of the object
and the nature of the surface with which the object is in contact. The bigger the temperature difference between a body and its surroundings, the faster the rate at which heat is transferred.
What are two causes of energy transfer?
Transferring energy
electrical work – charges moving due to a potential difference
.
heating – due to temperature difference caused
electrically or by chemical reaction.
What are the 4 ways energy can be transferred?
- Mechanically – By the action of a force.
- Electrically – By an electrical current.
- By radiation – By Light waves or Sound waves.
- By heating – By conduction, convection or radiation.
What does the total amount of energy transferred by an appliance depend on?
The amount of energy an appliance transfers depends on
how long the appliance is switched on for and the power of the appliance
. Work is done when charge flows in a circuit.
What is the formula for energy transferred?
The formula which links energy transferred, power and time, and the formula which helps you calculate the energy transferred is as follows:
Energy transferred = power x time.
What appliances transfer electrical energy into heat?
An electric fire, a cooker, a toaster and an electric kettle
all convert electrical energy into heat energy. The power of an appliance is the rate at which energy is transferred.
What is energy transfer by heat?
Heat is the transfer of
energy from a warmer object to a cooler object
. For example, a lighted match (higher temperature object) will transfer heat to a large pan filled with lukewarm water (lower temperature object).
What is energy transfer rate?
1.8
Power
is a measure of energy transfer rate. It is useful to talk about the rate at which energy is transferred from one system to another (energy per time). This rate is called power. One joule of energy transferred in one second is called a Watt (i.e., 1 joule/second = 1 Watt).
What is energy transferred from?
Energy can be transferred mechanically through the
movement of the parts in machines
, and when the motion or position of an object changes. Sound waves and seismic waves (formed during earthquakes) are mechanical waves that transfer energy through materials and from place to place.
What slows down the rate of energy transfer?
Materials that do not allow heat conduction to happen quickly are called
insulators
. These are things like plastics, wood and materials that contain trapped air or other gases. We can use insulators to decrease the rate of heat transfer. Convection occurs in fluids and is the reason that hot air rises.
What are the 3 ways to transfer energy?
There are three types of thermal energy transfer:
conduction, radiation, and convection
.
How is energy transferred in a washing machine?
A washing machine has an input energy of 30 000 J and
converts 26 500 J of energy into kinetic energy of the drum and thermal energy of the water
. The remaining energy dissipates to the surroundings as sound and heat energy.
What happens whenever energy is transferred between stores?
The energy transfer occurs by
convection (particle movement) and by radiation of heat and light
. The battery’s energy can be shifted to a kinetic store in a spinning motor by electrical work. Energy stores can be concentrated, like in a kettle of boiling water.
