Equations

Question 1

Speed

Answer 1

Distance/time (m/s)

Question 2

Acceleration

Answer 2

Change in speed/ time taken (m/s2)

Question 3

Weight

Answer 3

Mass x gravity (N)

Question 4

Density

Answer 4

Mass/ volume (kg/m3)

Question 5

Force

Answer 5

Mass x acceleration (N)

(mv - mu)/t

Question 6

Hooke’s force

Answer 6

Spring constant x extension (N)

Question 7

Moment

Answer 7

Force x perp. distance from pivot (Nm)

Question 8

Momentum

Answer 8

Mass x velocity (m/s2)

P=mv

Question 9

Impulse

Answer 9

Ft= mv - mu

Force x time = mass x final velocity - mass x initial velocity

Question 10

Kinetic energy

Answer 10

1/2mv2 (J)

Question 11

G.P.E

Answer 11

Mgh (J)

Question 12

Efficiency

Answer 12

Useful energy output/ energy input x100

Useful power output/ energy input x100

Question 13

Work done (2)

Answer 13

Force x distance (J)

Power x time taken

Question 14

Power

Answer 14

Work done/ time taken (N)

Question 15

Energy

Answer 15

Power x time

Mass x specific heat capacity x change in temp.

Question 17

Pressure in solids

Answer 17

Force/ area (Pa or N/m2)

Question 18

Pressure in liquids

Answer 18

Density x gravity x height (Pa)

Question 19

Specific heat capacity

Answer 19

C= E/ m x change temp.

Question 20

Thermal capacity

Answer 20

E/ change in temp.

Question 21

Latent heat

Answer 21

L= E/ m

Question 22

Final speed

Answer 22

V = u + at

Final speed = initial speed + acceleration x time