Equations

Question 1

Power (joules/second)

Answer 1

Energy transferred/time

Question 2

Power (watts/second)

Answer 2

Work done/time

Question 3

Weight ( newtons)

Answer 3

Mass x gravitational field strength

Question 4

Power (electrical)

Answer 4

Potential difference x current

Question 5

Power (electrical 2)

Answer 5

(Current)2 x resistance

Question 6

Pressure (pascals 1 newton/m2)

Answer 6

Force/surface area

Question 7

Density (kg/m3)

Answer 7

Mass/volume

Question 8

Efficiency (power)

Answer 8

Useful power output/total power input

Question 9

Efficiency

Answer 9

Useful output energy transfer/total input energy transfer

Question 10

Force applied to a spring (newtons)

Answer 10

Spring constant x extension

Question 11

Distance (meters)

Answer 11

Speed x time

Question 12

Kinetic energy

Answer 12

0.5 x mass x (speed)2

Question 13

Work done

Answer 13

Force x distance

Question 14

Moment of a force

Answer 14

Force x distance

Question 15

Acceleration

Answer 15

Change in velocity/time taken

Question 16

Resultant force

Answer 16

Mass x acceleration

Question 17

Momentum

Answer 17

Mass x velocity

Question 18

Gravitational potential energy

Answer 18

Mass x gravitational field strength x height

Question 19

Wave speed

Answer 19

Frequency x wavelength

Question 20

Charge flow

Answer 20

Current x time