Units & Equations

Question 1

What is the unit for density?

Answer 1

g/cm3 or kg/m3

Question 2

What is the unit for charge flow?

Answer 2

Columbs, C

Question 3

What is the equation relating pressure, force and area?

Answer 3

pressure = force / area

Question 4

What is the unit for resistance?

Answer 4

Ohms

Question 5

What is the equation relating power, work done and time?

Answer 5

Power = work done / time or Work done = power x time

Question 6

What is the unit for speed?

Answer 6

m/s

Question 7

What is the equation relating power, current and resistance?

Answer 7

Power = current^2 x resistance

Question 8

What is the unit for gravitational potential energy?

Answer 8

J

Question 9

What is the unit for mass?

Answer 9

kg

Question 10

What is the unit for force?

Answer 10

Newtons

Question 11

What is the unit for moment?

Answer 11

Nm

Question 12

What is the equation for efficiency?

Answer 12

efficiency = useful power/energy / total power/energy

Question 13

What is the unit for weight?

Answer 13

N (it is a force)

Question 14

What is the unit for momentum?

Answer 14

kgm/s

Question 15

What is the equation relating wave speed, frequency and wavelength?

Answer 15

wave speed = wavelength x frequency

Question 16

What is the equation relating power, energy transferred and time?

Answer 16

Power = energy transferred / time

Question 17

What is the equation that relates energy transferred, power and time?

Answer 17

Energy transferred = power x time

Question 18

What is the equation relating charge flow, current and time?

Answer 18

Charge flow = current x time

Question 19

What is the equation for gravitational potential energy?

Answer 19

G.P.E = mass x gravity x height

Question 20

What is the unit for acceleration?

Answer 20

m/s2

Question 21

What is the equation relating work done, force and distance?

Answer 21

work done = force x distance

Question 22

What is the unit for pressure?

Answer 22

N/m2 or Pa

Question 23

What is the equation relating force, mass and acceleration?

Answer 23

force = mass x acceleration

Question 24

What is the unit for wavelength?

Answer 24

m

Question 25

What is the unit for potential difference?

Answer 25

Volts, V

Question 26

What is the equation relating potential difference, current and resistance?

Answer 26

Potential difference = current x resistance

Question 27

What is the unit for work done?

Answer 27

J or Nm

Question 28

What is the unit for wave speed?

Answer 28

m/s

Question 29

What is the equation relating acceleration, change in velocity (speed) and time?

Answer 29

acceleration = change in speed / time taken

Question 30

What is the equation relating force in a spring. spring constant and extension?

Answer 30

force = spring constant x extension

Question 31

What is the equation that relates moment, force and distance?

Answer 31

Moment = force x distance

Question 32

What is the equation relating momentum, speed and mass? (Higher Tier Only)

Answer 32

momentum = speed x mass

Question 33

What is the unit for power?

Answer 33

Watt, W

Question 34

What is the equation relating weight, mass and gravitational field strength?

Answer 34

weight = mass x gravitational field strength

Question 35

What is the equation that relates energy transferred, potential difference and charge flow?

Answer 35

Energy transferred = potential difference x charge flow

Question 36

What is the unit for current?

Answer 36

Amps, A

Question 37

What is the unit for frequency?

Answer 37

Hz

Question 38

What is the equation relating power, potential difference and current?

Answer 38

Power = potential difference x current

Question 39

What is the unit for kinetic energy?

Answer 39

J, Joules (all energy has units Joules)

Question 40

What is the equation that relates density, mass and volume?

Answer 40

density = mass / volume

Question 41

What is the equation relating speed, distance and time?

Answer 41

Distance = speed x time or Speed = distance / time

Question 42

What is the equation for kinetic energy?

Answer 42

kinetic energy = 1/2 x mass x speed^2