Formulas

Question 1

Speed

Answer 1

Speed = distance / time

Question 2

Acceleration

Answer 2

Acceleration = final velocity - initial velocity / time taken

Question 3

Momentum

Answer 3

Momentum = mass x velocity

Question 4

Force (N)

Answer 4

Force = Change in momentum / time taken

Question 5

Resultant force

Answer 5

Resultant force = mass x acceleration

Question 6

Weight

Answer 6

Weight = mass x gravitational strength (9.8)

Question 7

Efficiency of device

Answer 7

Efficiency of device = useful energy (output) / total energy supplied (input)

Question 8

Power in terms of current and voltage

Answer 8

Power = current x voltage

Question 9

Gravitational potential energy

Answer 9

GPE = (MGH) mass x gravitational field strength (9.8) x change in height

Question 10

Kinetic energy

Answer 10

Kinetic energy = 0.5 x mass x velocity

Question 11

Elastic potential energy

Answer 11

Elastic potential energy = 0.5 x spring constant x extension^2

Question 12

Power in terms of energy and time

Answer 12

Energy / time

Question 13

Power in terms of current and resistance

Answer 13

Current^2 x resistance

Question 14

Work done

Answer 14

Force x distance

Question 15

Power in terms of work done

Answer 15

Power = work done / time

Question 16

Wave speed

Answer 16

Wave speed = frequency x wavelength

Question 17

Charge flow

Answer 17

Charge flow = current x time

Question 18

Density

Answer 18

Density = mass / volume

Question 19

Force applied to spring

Answer 19

Spring constant x extension

Question 19

Voltage

Answer 19

Current x resistance

Question 19

Energy

Answer 19

Voltage x charge

Question 19

thermal energy

Answer 19

mass x specific heat capacity x temp change

Question 20

Velocity

Answer 20

Velocity = displacement / time

Question 21

Pressure

Answer 21

Pressure = force / area