**Energy**Energy = Work Done = Force x distance moved in the direction of Force

Kinetic Energy (K.E.) = 1/2mv

^{2}where m is mass and v is velocity (JOULES)

Potential Energy (P.E.) = mgh where m is mass, g is gravity and h is height (JOULES)

Power = Energy / time = Work done/Time (WATTS)

Efficiency = Power Out/Power In (Remember Pout over Pin) = Energy Out/ Energy In (per second)Multiply by 100 to get percent.

**Heat Transfer**Conduction

* Metals, free electrons dominate

* Solids, domino effect on vibrations

Convection

* Heat --> Kinetic Energy --> Expansion

* Less dense rises

Radiation

*Electromagnetic Waves can travel in a vacuum

*Sun'slight is heat

Uses of expansion in everyday life --> Bimetallic strip in thermostats

**Forces**Newtons Laws

* 1st Law = Law of inertia

* 2nd Law = Resultant Force = ma (with m being mass and a being acceleration)

* 3rd Law = Action & Reaction (every action has an equal and oppisite reaction)

Force --> Weight = mg (g=10m/s on earth)

Density = mass/volume (kg/m

^{3})

Hookes law - extension is directly proportional to load (Springs)

F =mg =K.e.)

__Moments__Clockwise moment = anti-clockwise moment

Moment = Force x Distance from Pivot

Centre of Gravity / Mass = Point where the force of gravity acts.

Pressure = Force/Area (N/m

^{2}= Pa)

* Liquids are not compressible therefore pass on the pressure applied.

__Motion__Speed = Distance / Time Velocity = Displacement/Time

Equations of motion (Triple Awars)

1. v = u + at

2. s = ut + 1/2at

^{2}3. v

^{2}=u

^{2}+2as

* In a displacement time graph the gradient (slope) = velocity

* In a velocity time graph the gradient = acceleration & the area under the line is the distance travelled.

Momentum = mass x velocity = mv (Ns=Kgm/s)

if abody movesin a circle then a force muct be applie to keep it moving in that circle. This is the CENTRIPETAL FORCE.

Ball on a string -->force is due to the tension in the string. if the string breaks the ball flies off at a tangent

F = mv

^{2}/r

__Waves__Waves can be transverse or longitudinal.

frequency = number of waves per second (Hz [Hertz] )

Wave equation --> v=f(lambda) lambda looks like an upside down y, I don't know how to do it on the computer)

* Sound is a longitudinal wave. A human can hear 20Hz --> 20KHz (or 15KHz if they are elderly)

* Sound cannot travel in a vacuum

* Frequency controls pitch, Amplitude controls loudness

*Light is part of the electromagnetic spectrum

* These waves travel at c= 3x10

^{8}m/s in a vacuum

* Light travels in straight lines --> this is what causes shadows.

Total Internal Reflection (TripleAward)

This is when light isreflected back into the glass because the angle of incidence = criticle angle and then the refracted angle = 90

White light is dispersed in the colours of the rainbow

(Red --> Orange --> Yellow --> Green --> Blue --> Indigo --> Violet)

__Electricity__I(amps) =Current = Change Q / CHange T

RESISTORS IN A SERIES ADDeg Resistance = 1/R1 + 1/R2 + 1/R3 etc etc

Resistors in parallel --> 1/R = 1/R1 + 1/R2 + 1/R3 etc

Ohms law --> V=IR

W = Energy =QV

Power = Energy/ Time =IV =V

^{2}/R = I

^{2}R

In a plug

*Green and Yellow is the EARTH wire and goes to the top pin

* Blue is the NEUTRAL wire and goes to the left

* Brown is the LIVE wire and goes to the right pin (or wherever the fuse is located)

Double Insulation is represented by a square inside a square.

Cost of electricity --> 1 unit = 1Kwhour

__Earth and Space__Force of attraction= GM

_{1}M

_{2 }/ r

^{2}

Want me to elaborate on/explain anything ?

Also, remember to look at this !

This community is well dead like.

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