Formulas

Question 1

If transformers are 100% efficient, give the formula

Answer 1

Ip x Vp = Is x Vs
s - secondary
p - primary

Question 2

Refractive index

Answer 2

Speed of light in a medium\
Speed of light in a vacuum

Question 3

Resistors in parallel

Answer 3

1/ R total = 1/ R1 + 1/ R2

Question 4

Spring constant

Answer 4

K = F/X

Question 5

Transformers

Answer 5

Vs / Vp = Ns / Np

Question 6

Efficiency

Answer 6

Useful output / total input

Question 7

Kinetic energy

Answer 7

1/2 mass x velocity squared

Question 8

Impulse of a force

Answer 8

FT = MV - MU
U - initial velocity
V - final velocity

Question 9

Power

Answer 9

P = W/T
W - work done
T - time taken

Question 10

Wave speed

Answer 10

Frequency x wavelength

Question 11

Boyles law

Answer 11

p1 x v1 = p2 x v2

Question 12

Force

Answer 12

Mass x acceleration

Question 13

Law of reflection

Answer 13

Angle of incidence = angle of reflection

Question 14

Pressure in a liquid

Answer 14

Density x gravity x height

Question 15

Momentum

Answer 15

Mass x velocity

Question 16

Weight

Answer 16

Mass x gravitational field strength
Gravitational field strength - 10

Question 17

Refractive index

Answer 17

Sin i / sin r

Question 18

Frequency of a wave

Answer 18

Occurrences \ time period

Question 19

Acceleration

Answer 19

(V - U) / t

Question 20

Moment of a force

Answer 20

Mass x perpendicular distance from pivot

Question 21

Specific heat capacity

Answer 21

Change in thermal energy = mass x specific heat capacity x change in temperature

Question 22

Pressure

Answer 22

Force /area

Question 23

Work done

Answer 23

Force x distance

Question 24

Density

Answer 24

Mass /volume

Question 25

Gravitational Potential energy

Answer 25

Mass x gravity x height

Question 26

Critical angle

Answer 26

sin C = 1/ refractive index

Question 27

Resistance

Answer 27

Voltage / current

Question 28

Resistors

Answer 28

R = R1 + R2

Question 29

Velocity

Answer 29

Distance / time

Question 30

Principle of moments

Answer 30

Total clockwise moments = total anti-clockwise moments

Question 31

Wave frequency

Answer 31

Number of waves / time taken

Question 32

Orbital speed

Answer 32

(2 x pie x radius) / time

Question 33

Current formula

Answer 33

Charge / time

Question 34

SI unit for energy transfer

Answer 34

J/s

Question 35

hubble constant

Answer 35

v = HOd

Question 36

acceleration due to gravity on earth

Answer 36

9.8 m/s squared

Question 37

time period

Answer 37

1 / frequency

Question 38

power

Answer 38

energy / time

Question 39

voltage

Answer 39

I x R remember VIR for resistance aswell

Question 40

energy transferred

Answer 40

I x V x t

Question 41

gravitational acceleration (gravity)

Answer 41

9.8, NOT 10

Question 42

hubbles constant

Answer 42

2.2 x 10^-18

Question 43

thermal energy

Answer 43

m x c x change in t

Question 44

the conservation of momentum

Answer 44

m1u1 + m2u2 = m1v1 + m2v2

Question 45

the equation that links gravitational potential energy and kinetic energy

Answer 45

Decrease in PE= Increase in KE increase in PE = decrease in KE

Question 46

snells law

Answer 46

n1 sin θ1= n2 sinθ2