Equations To Memorise

Question 1

Weight =

Answer 1

Mass x gravitational field strength

Question 2

Force applied to a spring

Answer 2

Spring constant x extension

Hooke’s law

Question 3

Acceleration

Answer 3

Change in velocity / time taken

Question 4

Momentum

Answer 4

Mass x velocity

Question 5

Gravitational potential energy

Answer 5

Mass x height x gravitational field strength

Question 6

Power

Answer 6

Work done / time

Question 7

Efficiency

Answer 7

Useful power output / total power output

Question 8

Charge flow

Answer 8

Current x time

Question 9

Power (electricity)

Answer 9

Potential difference x current

Question 10

Energy transfer

Answer 10

Power x time

Question 11

Density

Answer 11

Mass / volume

Question 12

Work done

Answer 12

Force x distance along the line of action of the force

Question 13

Distance travelled

Answer 13

Speed x time

Question 14

Resultant force

Answer 14

Mass x acceleration

Question 15

Power (3)

Answer 15

Energy transferred / time

Question 16

Efficiency (2)

Answer 16

Useful output energy transfer / total input energy transfer

Question 17

Wave speed

Answer 17

Frequency x wavelength

Question 18

Potential difference

Answer 18

Current x resistance

Question 19

Power (electricity 2)

Answer 19

Current2 x resistance

Question 20

Energy transferred (electricity)

Answer 20

Charge flow x potential difference

Question 21

Pressure

Answer 21

Force normal to surface / area of the surface

Question 22

Moment of a force

Answer 22

Force x distance to pivot

Question 23

Kinetic energy

Answer 23

1/2 x mass x velocity2

Question 24

Uncertainty

Answer 24

Range / 2