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PHYSICS, Electric circuits - Coggle Diagram
PHYSICS
energy
energy stores: magnetic,thermal,chemical,kenetic, electrostatic,elastic potential,gravitatinal potential and nucular.
magnetic:The energy stored when repelling poles have been pushed closer together or when attracting poles have been pulled further apart.
thermal: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.
chemical:The energy stored in chemical bonds, such as those between molecules.
kenetic:The energy of a moving object.
electrostatic:The energy stored when repelling charges have been moved closer together or when attracting charges have been pulled further apart.
elastic potential: The energy stored when an object is stretched or squashed.
gravitatinal potential:The energy of an object at height.
nucular:The energy stored in the nucleus of an atom.
Work, power and efficiency
energy and work:
When a force causes a body to move, work is being done on the object by the force. Work is the measure of energy transfer when a force (F) moves an object through a distance (d).
So when work is done, energy has been transferred from one energy store to another, and so:
energy transferred = work done
Energy transferred and work done are both measured in joules (J).
Energy and power
When work is done on an object, energy is transferred. The rate at which this energy is transferred is called power. So the more powerful a device is, the more energy it will transfer each second.
Energy and heating
As well as transferring energy from one store to another, energy is transferred or transmitted from place to place. As it moves through a substance, energy is transmitted by conduction, convection or radiation.
Conduction
The aluminium base of a pan, the copper in the wires from a plug and the steel of a bell are all conductors.
A conductor is a material that allows internal (thermal) energy to be transmitted through it easily.
All metals are good conductors. When one end of a metal rod is put into a fire, the energy from the flame makes the ions in the rod vibrate faster. Since the ions in the solid metal are close together, this increased vibration means that they collide with neighbouring ions more frequently. Energy is passed on through the metal by these collisions, transmitting the energy. More frequent collisions increase the rate of transfer.
electricity
Electric circuits
The following symbols show the different components that can be found in an electrical circuit.
Individual circuit symbols in one sheet including, open switch, closed switch, lamp, voltmeter, ammeter, resistor, variable resistor, LDR, thermistor, diode, LED, cell, battery and fuse.
Components
Some of the more common components are:
Switch
A switch used to turn a circuit on (closed) and off (open).
Lamp
An electrical current heats the filament in a bulb so that it gives out light.
Fixed resistor
A resistor restricts or limits the flow of electrical current. A fixed resistor has a resistance that does not change.
Variable resistor
Moving the position of the slider on this resistor, changes the resistance. A variable resistor is used in some dimmer switches and volume controls.
Thermistor
The resistance of a thermistor depends on its temperature. At low temperatures, the thermistor has a high resistance. As the temperature increases, the resistance decreases. A thermistor can be used in thermostats or heat activated fire alarms.
Light-dependent resistor (LDR)
The resistance of a LDR depends on light intensity. At low light levels, the LDR has a high resistance. As the light intensity increases, the resistance decreases. A LDR can be used as a sensor in cameras or automatic lights that come on when it gets dark.
Semiconductor diode
A semiconductor diode allows current to flow in one direction only. Current will not flow in the other direction. Diodes are used to convert an alternating current into a direct current.