# Physics Paper 2 Equations

?

## Section 4 - Forces and energy

When a FORCE moves an object through a DISTANCE, WORK IS DONE on the object and ENERGY IS TRANSFERRED.

Work done (j) = Force (n) x Distance moved in the direction of the force (m)
E = F x D

Power (W) = Work Done (J) / Time taken (S)

P = E / T

Moment of a force (nm) = Force (N) x Distance (m)

the sum of clockwise moments = the sum of anticlockwise moments

1 of 7

## Section 5 - Electricity and circuits

Charge (c) = Current (A) x Time(s)

Q = I x T

Energy Transferred (j) = Charge moved (c) x Potential Difference (v)

E = Q x V

potential difference (v) = Current (A) x Resistance (Ohms)

V = I x R

Energy Transferred (J) = Current (A) x Voltage (V) x Time (s)

E = I x V x T

2 of 7

## Section 5 - Electricity and circuits Cont...

Power (w) = Energy Transferred (J) / Time (s)

P = E / T

Electrical Power (W) = Current (A) x Potential Difference (V)

P = I x V

Power (w) = Current (A)^2 x Resistance (ohms)

P = I^2 x R

3 of 7

## Section 6 - Electric and Magnetic Fields

Force (N) = Magnetic Flux Density (T, tesla or N/Am) x Current (A) x Length (m)

F = B x I x L

ELECTROMAGNETIC INTRODUCTION: The INDUCTION of a POTENTIAL DIFFERENCE (and CURRENT if there is a COMPLETE CIRCUIT) in a wire which is experiencing a CHANGE IN MAGNETIC FIELD.

Vp x Ip = Vs x Is

Vp / Vs = Np / Ns

4 of 7

## Section 7 - Matter

Density = Mass / Volume

Change in thermal energy (j)= Mass(kg) x Specific heat capacity(J/kgC) x Change in Temperature (C)

Q = M x C x θ

Thermal Energy (J) = Mass (kg) x Specific Latent Heat (J/kg)

Q = M x L

P1V1 = P2V2

5 of 7

## Section 7 - Matter Part 2

Force (N) = Spring Constant (N/m) x Extension (m)

F = K x X

Energy transferred in stretching (j) = 0.5 x Spring Constant (N/m) x Extension^2 (m^2)

E = 0.5 x K x X^2

Pressure (Pa)  = Force (N) / Area (m^2)

P = F / A

6 of 7

## Section 7 - Matter Part 3

Pressure due to a column of liquid (Pa) = height x Density of the liquid (kg/m^3) x Gravitational field strength

P = H x p x G

7 of 7