Physics Equations

Movement and Position:

Distance = Speed x Time

Acceleration = Change in Velocity / Time Taken

Forces and Movement:

Force = Mass x acceleration

Weight = Mass x Gravitation Field Strength

Momentum:

Momentum = Mass x Velocity

Force = Change in Momentum / Time Taken

Momentum BEFORE Collision = Momentum AFTER Collision

The Turning Effect of Forces:

Moment of a Force = Force x Perpendicular Distance from Pivot

Sum of ANTIclockwise Moments = Sum of Clockwise Moments

Astronomy:

Orbital Speed = (2 x Pi x Orbital Radius) / Time Period

Newton's Laws of Motion:

• A body will continue to move in a straight line at a steady speed unless a resultant force was acting on the body. If the forces acting on an object are balanced, then a stationary object stays in one place and a moving object continues to move in just the same way as it did before the force was applied.

• The bigger the force acting on an object, the faster the object will speed up. Objects with greater mass require bigger forces than those with smaller mass, to make them accelerate at the same rate.

• For every action, there is an equal and opposite action.

Mains Electricity:

Power = Current x Voltage

Energy = Power x Time

Energy = Current x Voltage x Time

Current and Voltage in Circuits:

Charge = Current x Time

Electrical Resistance:

Voltage = Current x Resistance

Properties of Waves:

Wave Speed = Frequency x Wavelength

Frequency = 1 / Time Period

Light Waves:

Refractive Index = Sin i / Sin r

Sin Critical Angle = 1 / Refractive Index

Energy Transfers:

Efficiency = (useful energy output / total energy input) x 100%

Work and Power:

Work Done = Force x Distance

GPE = Mass x GFS x Height

Kinetic Energy = 1/2 x Mass x Velocity²

Power = Work Done / Time Taken

Density and Pressure:

Density = Mass / Volume

Pressure = Force / Area

Pressure Difference = Height x Density x GFS

Solids, Liquids and Gases:

Pressure(1) x Volume(1) = Pressure(2) x Volume(2)

Temperature in K = Temperature in ˚C + 273

Temperature in ˚C = Temperature in K - 273

Pressure(1) / Temperature(1) = Pressure(2) / Temperature(2)     [must be in K]

Electric Motors and Electromagnetic Induction:

Input Voltage / Output Voltage = Turns on Primary Coil / Turns on Secondary Coil