Equations

Question 1

Acceleration, change in velocity and time taken

Answer 1

(v-u)
A = ——
t

Question 2

Weight, mass and gravitational field strength

Answer 2

Weight = mass x gravitational field strength

Question 3

Acceleration, mass and resultant force

Answer 3

Resultant force = mass x acceleration

Question 4

Initial speed, acceleration, final speed and distance

Answer 4

Final speed^2 = initial^2 + ( 2 x acceleration x distance)

v2 = u2 + (2as)

Question 5

Applied force, spring constant and elastic extension

Answer 5

Force = spring constant x elastic extension

Question 6

Momentum

Answer 6

Total momentum before and after collision are equal

Question 7

Current, voltage and resistance

Answer 7

Voltage = current x resistance

Question 8

Charge, voltage and energy

Answer 8

Energy = charge x voltage

Question 9

Frequency and time period

Answer 9

1
Frequency —————
Time period

Question 10

Refractive index, sine i and sine r

Answer 10

Refractive index = sine i / sine r

Question 11

Refractive index, sine c

Answer 11

1
Refractive index = ————-
Sine c

Question 12

Efficiency, useful energy and total energy

Answer 12

Useful energy
Efficiency = ——————-
Total energy

Question 13

Density, volume and mass

Answer 13

Density =mass / volume

Question 14

Work done, distance and force applied

Answer 14

Work = force x distance

Question 15

Gravitational potential energy, mass, height and gravitational field strength

Answer 15

GPE = m x g x h

Question 16

Kinetic energy, speed

Answer 16

Kinetic = 1/2 x mass x speed^2

Question 17

Power, work and time taken

Answer 17

Work done = power x time taken

Question 18

Pressure, force and area

Answer 18

Force = pressure x area

Question 19

Pressure ( before and after), volume ( before and after )

Answer 19

P1V1 = P2V2

Question 20

Pressure ( before and after), temperature ( before and after)

Answer 20

P1 P2
— = —
T1 T2

Question 21

Mass(M), change in thermal energy (ΔQ), heat capacity (c), change in temperature (ΔT)

Answer 21

ΔQ = m x c x ΔT

Question 22

Change in wavelength, velocity of a galaxy, reference wavelength and speed of light

Answer 22

Change in wavelength
———————————
Reference wavelength

=

Velocity of a galaxy
—————————
Speed of light