Physics 2

Energy is neither created or destoryed, it is converted from one form to another.

Efficiency = Useful energy output / total energy input 

               x 100

Is the transfer of thermal energy through a substance without the substance moving

Is the transfer of heat energy through fluids by the upward movement of warmer, less dense region in the fluid being pushed away by the colder and therefore denser fluid.

Is the transfer of heat energy in the form of infrared waves. The only method of hear transfer through a vacuum.

Work DOne (joules) = Force (Newtons) x DIstance (metres) 

Energy transferred = Work Done

GPE (Joules) = mass (kg) x gravitational field strength x height (m)

Kinetic Energy = 1/2 x mass x speed squared

Is the rate of transfer of energy or the rate of doing work

Power = Work Done / TIme

Density (kg/m3) = mass / volume

Pressure (Pascals)= Force / Area

In solds exert downward force

In liquid at any point act in all directions and increases with depth

Pressure DIfference = Height (m) x Density (kg/m3) x g

Particles in matter ar extremely small and in fluids they are in continous state of rapid random motion. 

For a fixed amount of gas at a constant temperature pressure is inversely proportionate to the volume

Pressure 1 x Volume 1 = Pressure 2 x Volume 2

P1/P2 = V2/ V1

0 degress Kelvin = -273 degrees celcius

For a fixed amount of gas at constant volume 

P1/T1 = P2/T2

Therefore pressure is proportionate to kelvin Temperature

Transfer energy from one place to another without transfering matter

The distance between corresponding points in the wave

The maximum displacement of a part of the medium from its rest position

The time for one complete cycle of the wave form

The number of cycles of waveform per second

Frequency = 1/period

Wave speed = Frequency x wavelength

ANGLE OF INCIDENCE = ANGLE OF REFLECTION 

n = sini/ sin r

Run                                          Radio Waves

Miles                                        Micro Waves

In                                               Infrared

Very                                          Visible Light

Uncomforatble                        Ultraviolet 

eXtreme                                     X-rays

Games                                     Gamma rays

Are substances of the same element with the same number of protons but different number of neutrons. 

A radioactive substance has an unstable nuclei and will emit radiation to make the nucleus more stable

Is a random process when the nucleus emits a radioactive particle under-goes a change in structure except gamma radiation as has no mass or charge

Half life of radioactive isostope is the time taken for half the original number of unstable nuclei to decay

The time taken for the activity of a radioactive substance to fall to half its original value. 

Becquerels (Bq)

Can be split into lighter element quite easily

A current in a coil of wire produces a magnetic field

Made stronger:

1) Increasing current

2) Increasing number of turns in coil

3) By winding coil around a magnetic material

When a conductor is in a changing magnetic field a voltage will be induced in the conductor or when it moves through a magnetic field. If the conductor is part of a closed electric circuit then the induced voltage will cause a current to flow. 

Function = change size of an alternating voltage. Done by having two separate coils with different numbers of turns. 

Input Voltage/ Output voltage = Primary turns / Secondary Turns