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Physics Keywords
Keywords for junior cert physics
Term | Definition |
---|---|
Speed | Distance travelled by an object in a unit of time |
Velocity | Speed of an object in a given direction |
Acceloration | Change in Speed/Time taken |
Force | Causes a stationary object to move |
Friction | A force that opposes the sliding motion of an object when in contact with another object |
Lubrication | Used to reduce friction between two substances in contact |
Weight | The pull of the earth on an object |
Hooke's law | The extension of an elastic body is directly proportional to the force causing the extension |
Lever | A rigid body that can turn about a fixed point called the fulcrum |
Law of the lever | When a lever is balanced the sum of its clockwise moments = the sum of its anti-clockwise moments |
Centre of gravity | A point in an object where all its weight appears to act |
Pressure | Amount of force acting on a unit of area |
Work | Force x Distance |
Energy | The ability to do work |
Power | Rate at which work is done |
Latent Heat | Change in state but not a change in temperature |
Dispersion | The spreading of light into its different colours |
Reflection | The bouncing of light off a surface |
Refraction | The bending of light as it passes through another medium |
Sound | A form of energy produced when particles in an object vibrate |
Magnetic Force | Force of attraction or repulsion between 2 magnets |
Magnetic Field | The region around a magnet in which the magnetic force can be detected |
Insulator | A material through which charge cannot flow |
Conductor | A material through which charge can flow |
Alternating Current | A current that flows in a continually changing direction |
Direct current | A current that flows in one direction only |
Diode | Allows current to flow |
LED | Light Emitting Diode |
LDR | Light Dependent Resitor |
Ohm's Law | Voltage is directly proportionate to current |
Echo | Reflection of sound |