How many g is 1kg
1000g
What are the 4 types of energy transfer?
Radiation, Electrical, Heating and Mechanical
What are examples of Energy transfer by Radiation and what is it?
- energy tranferred as a wave
- Sound, gamma rays, x rays, ultra violet, light, infra red, microwaves and radio waves
What are examples of Energy transfer by Electricity and what is it?
- electrical currents moving due to a potential difference
- e.g a battery transfers electrical energy to a light bulb
What are examples of Energy transfer by Heating and what is it?
- due to temperature difference caused electrically or by chemical reaction
- e.g transferring heat into a bottle by putting hot water in it
What are examples of mechanical energy transfer and what is it?
- a force moving an object through a distance
- e.g transferring energy into an object by pushing/pulling it
What are the 8 types of energy store?
Magnetic, kinetic, nuclear, electrostatic, chemical, thermal, elastic potential and gravitational potential
What is a kinetic energy store?
- Anything moving has a store of kinetic energy
- e.g Runners, buses, comets.
What is a nuclear energy store?
- the energy stored in the nucleus of an atom
- e.g Uranium nuclear power, nuclear reactors.
What is an electrostatic energy store?
- The energy stored when repelling charges have been moved closer together or when attracting charges have been pulled further apart.
- e.g Thunderclouds, Van De Graaff generators.
What is a chemical energy store?
- The energy stored in chemical bonds, such as those between molecules
- e.g Foods, muscles, electrical cells
What is a thermal energy store?
- anything warmer than -273°C has thermal. -273°C is called absolute zero because all the particles stop moving.
- The total kinetic and potential energy of the particles in an object, in most cases this is the vibrations - also known as the kinetic energy - of particles. In hotter objects, the particles have more internal energy and vibrate faster
- e.g Human bodies, hot coffees, stoves or hobs. Ice particles vibrate slower, but still have energy
What is an elastic potential energy store?
- The energy stored when an object is stretched or squashed.
- e.g Drawn catapults, compressed springs, inflated balloons
What is a gravitational potential energy store?
- The energy of an object at height, which is being pulled down by gravity
- e.g Aeroplanes, kites, mugs on a table
What is a magnetic energy store?
- The energy stored when repelling poles have been pushed closer together or when attracting poles have been pulled further apart.
- Fridge magnets, compasses, maglev trains which use magnetic levitation
Draw a sankey diagram for this information: In a lightbulb, 500J were transferred to the bulb, 75J were used as light energy and 425J was used as heat energy
Answer is in folder
What is the equation to find the efficiency percentage of a device?
Efficiency percentage of device= (useful energy transferred by the device ➗ total energy supplied to the device) ✖️100
What is the equation to find the efficiency of a device?
Efficiency of device= (useful energy transferred by the device ➗ total energy supplied to the device)
A light bulb radiates 20 J of energy as light for every 100 J of electrical energy supplied to it. Calculate the energy wasted by the light bulb for every 100J of electrical energy supplied to it.
80J
A light bulb radiates 20 J of energy as light for every 100 J of electrical energy supplied to it. Calculate the percentage efficiency of the light bulb
20%
An energy saving lightbulb wastes 5J of energy for every 20 J of energy it radiates as light . How much energy is supplied to it for every 20 J of energy it radiates as light?
25J
An energy saving lightbulb wastes 5J of energy for every 20 J of energy it radiates as light. Calculate the lights efficiency.
80%
What is power?
- power is how much energy is transferred per second
- it is measured in Joules per second or Watts
What is the equation to find the amount of power in something?
Power (watts) = energy transferred (in J) ➗ time taken in seconds
