Physics Formula

Question 1

Final Velocity

Answer 1

v=u+at (initial velocity + acceleration * time)

Question 2

Displacement under constant acceleration

Answer 2

s=ut+(at**2)/2

Question 3

Relations between velocity, acceleration, and displacement

Answer 3

V** 2=u** 2+2as (s is displacement)

Question 4

Newton’s second Law

Answer 4

F=ma (mass * acceleration)

Question 5

Work done by a force over a displacement

Answer 5

W=Fd (W in J and d in m)

Question 6

General Change in energy

Answer 6

delta E = Fd

Question 7

Power

Answer 7

P=W/t (P in watts)

Question 8

Kinetic Energy

Answer 8

KE= 1/2 mv**2 (KE in J)

Question 9

Gravitational potential energy

Answer 9

PEg= mgh

Question 10

Efficiency

Answer 10

Efficiency = (useful energy output / total energy input)

Question 11

Hooke’s Law

Answer 11

F = ox (Force in spring = spring constant * extension) (k in N/m and x in m)

Question 12

Elastic potential energy ( energy stored in stretched spring)

Answer 12

E = 1/2 kx**2

Question 13

Momentum

Answer 13

p = mv (kg*m/s)

Question 14

Impulse; change in momentum

Answer 14

J = F delta t (force * time)

Question 15

Conservation in collisions

Answer 15

m1v1 + m2v2 = m1v1 + m2v2 (avant = après)

Question 16

Centripetal force

Answer 16

Fc = (mv**2)/r = mrw (force towards center in circular motion in N) (w is angular speed)

Question 18

Period

Answer 18

T = 1/f

Question 19

Universal gravitation

Answer 19

F = G(m1m2/r**2) (force between two masses m1 et m2)

Question 20

Gravitational field

Answer 20

g = GM/r**2 (field around mass M)

Question 21

Wave speed

Answer 21

v = f*lamba (speed = frequency * wavelength)

Question 22

Frequency

Answer 22

f = 1/T

Question 23

Lens / mirror equation

Answer 23

1/f = (1/u) + (1/v) ( focal length, object distance, image distance)

Question 24

Magnification

Answer 24

m = v/u = (image size / object size)

Question 25

Charge flow

Answer 25

Q = I t (charge flow = current per time)

Question 26

Voltage potential difference

Answer 26

V = E/Q

Question 27

Ohm’s Law

Answer 27

V = IR

Question 28

Resistivity

Answer 28

R = pho * L/A (pho in ohm by m, L in m, and A in m **2)

Question 29

Power in electric circuits (4)

Answer 29

P = E/t = IV = I**2 * R = V**2/R

Question 30

Energy in circuits

Answer 30

E = VQ = IVt

Question 31

Resistance in series

Answer 31

R = R1 +R2 + …

Question 32

Resistance in parallel

Answer 32

1/R = 1/R1 + 1/R2 + …

Question 33

Magnetic force on current

Answer 33

F = BIL

Question 34

Force on a moving charge

Answer 34

F = qvB ( charge q moving at speed v in magnetic field B)

Question 35

If power in = power out

Answer 35

V1I1 = V2I2

Question 36

Transformer idéal

Answer 36

V1/V2 = N1/N2

Question 37

Ideal gas law

Answer 37

pV = nRT = m(R/M)T (pressure * volume = moles * gas constant + temperature or using mass and molar mass)

Question 39

Pressure

Answer 39

p = F/A (force per area) (Pa = N/m**2)