Physics formula

Question 1

Hookes law

Answer 1

Force = constant x extension

Question 2

Moment both formulas

Answer 2

Moment = force x distance to pivot at 90 degrees. or force 1 x distance 1 = force 2 tx distance 2

Question 3

How to calculate resultant force

Answer 3

make them chase each other then use pythagoras

Question 4

Force

Answer 4

force = mass kg x acceleration m/s^2

Question 5

Weight

Answer 5

Weight = mass x gravity

Question 6

Momentum

Answer 6

Momentum = mass x velocity

Question 7

Impulse

Answer 7

Impulse = force x contact time = change in momentum

Question 8

Velocity

Answer 8

velocity = distance/time

Question 9

Acceleration

Answer 9

Acceleration = change in velocity/change in time

Question 10

Distance in a speed time graph

Answer 10

Area under the graph

Question 11

Density

Answer 11

density = mass/volume

Question 12

Pressure in gas, both formulas

Answer 12

pressure = 1/volume or Pressure 1 x volume 1 = pressure 2 x volume 2

Question 13

Work

Answer 13

Work or change in energy = force x distance

Question 14

Potential Energy

Answer 14

Potential Energy = mass x gravity x Height

Question 15

Kinetic Energy

Answer 15

Kinetic Energy = ½ x mass x (velocity)2

Question 16

Power

Answer 16

Power = work done/time taken

Question 17

Pressure

Answer 17

Pressure = force/area

Question 18

Pressure in Liquids:

Answer 18

Pressure = density x gravity x depth

Question 19

Current

Answer 19

Current = Charge/ time I = Q/t

Question 20

potential difference (Voltage)

Answer 20

potential difference (Voltage) = work done/ charge

Question 21

e.m.f

Answer 21

e.m.f. = Work done/Charge

Question 22

(Ohm’s law) Voltage

Answer 22

(Ohm’s law) Voltage = current x resistance V = I R

Question 23

Resistance

Answer 23

resistance = voltage/current

Question 24

Power / energy transfer per unit time

Answer 24

Power = current x voltage

Question 25

Energy

Answer 25

Energy E = Voltage x current x time

Question 26

Resistors in series

Answer 26

R = R1 + R2

Question 27

Resistors in parallel R

Answer 27

R = R1 x R2 / R1 + R2

Question 28

Heat Energy

Answer 28

Heat Energy = mass x specific heat capacity x temperature change

Question 29

Efficiency

Answer 29

Efficiency = useful Energy (or power) output/Energy input x 100%

Question 30

Wave speed

Answer 30

Wave speed = frequency x wavelength

Question 31

Frequency of a wave

Answer 31

Frequency = number of oscillations / timetaken

Question 32

Refractive index

Answer 32

n = sin i/ sin r or 1/sin c

Question 33

speed of light and sound

Answer 33

Speed of light in a vacuum (air) = 3.0 x 108 m/s Speed of Sound in air= 330 to 350 m/s

Question 34

Transformer

Answer 34

Number of turns in primary coil/ Number of turns in secondary coil = Voltage in primary coil/ voltage in secondary coil

Question 35

Orbital speed

Answer 35

Orbital speed = circumference distance/period time

Question 35

Power watts

Answer 35

power input = power output or Vp x Ip = Vs x Is

Question 36

hubble constant

Answer 36

H = velocity / distance