Flashcards in Key equations Deck (24):

1

## Average speed =

### Distance / time

2

## Distance =

### Average speed x time

3

##
Acceleration =

And another version which starts with v^2 - u^2 = ...

###
Change in velocity / time taken

a= (v-u)/t

V^2 - u^2 = 2 x a x X

X stands for distance

4

## What is Newton’s second law? The equation for force?

### F=m x a

5

## Weight=

###
Mass x gravitational field strength

W = m x g

6

## What is Earths gravitational field strength?

###
10 N/kg

9.81 rounded

7

## Momentum =

###
Mass (kg) x velocity

P = m x v

8

## Change in gravitational potential energy (Joules)=

###
Mass x gravitational field strength x change in vertical height

^GPE = m x g x ^h

9

## Kinetic energy (Joules) =

### 1/2 x m x v^2

10

## Efficiency =

### Useful energy transferred / total energy supplied

11

##
Wave velocity =

State both equations

###
Wave velocity = frequency x wavelength

Wave velocity = distance / time

12

## What is the equation for force which includes momentum ?

###
Force = change in momentum / time

F = (mv - mu) / t

13

## What is the equation for work done?

### Work done = force x distance

14

## What is the equation for power? A measure of how quickly work done is being done

### Power = work done / time

15

## What is the equation for work done (measured in joules) ?

###
E = F x d

Work done in Joules= force in N x distance moved in direction of force

16

## What is the equation for power in watts?

###
P = E/t

Power = Energy transferred in joules / time

17

## What is the equation for energy transferred in joules?

###
E = Q x V

Energy transferred in joules = Charge in coulombs x potential difference in volts

18

## What is the equation for potential difference in volts?

###
V = I x R

Potential difference in volts = current in amps resistance in Ohms

19

## What is the equation for charge in coulombs (C)?

###
Q = I x t

Charge in coulombs = current in amps x time

20

## What is the equation (one out of 2) for power in watts, including potential difference in volts?

###
P = I x V

Power in watts = current in amps x potential difference in volts

21

## What is the equation (one out of 2) for power in watts,including resistance in ohms (measured with Greek letter Omega)?

###
P = I(squared) x R

Power in watts = current in amps (squared) x resistance in ohms

22

## What is the equation for density in kg/m(cubed) or g/cm(cubed)?

###
p (lower case Greek letter rho) = m / V

Density in kg/m(cubed) or g/cm(cubed) = mass in kg/ volume in m or cm (cubed)

23

## What is the equation for pressure in N/m(squared) or N/cm(squared)?

###
P = F/ A

Pressure in N/m or N/cm (squared) = Force in N / Area in m or cm (squared)

24