Physics Equations

Question 1

Const Acceleration: find distance

Answer 1

X = Xi + Vi t + 1/2 a t^2

Question 2

Const Acceleration: find final velocity (using time)

Answer 2

vf = vi + a t

Question 3

Const Acceleration: find final velocity (without time)

Answer 3

vf^2 = vi^2 + 2ax

Question 4

Const Acceleration: Find Average Velocity

Answer 4

Vavg = (vi + vo)/2

Question 5

Const Acceleration: Find Initial Velocity (with height in y direction given)

Answer 5

Vi = (2gh)^(1/2)

Question 6

Newton’s Second Law

Answer 6

F = ma

Question 7

Force of Gravity Between Two Objects

Answer 7

F = G(m1 m2)/r^2

Question 8

Inclined Plane: Force in x Direction

Answer 8

Fx = m g sin(O)

Question 9

Inclined Plane: Normal Force

Answer 9

Fn = m g cos(O)

Question 10

Circular Motion: Centripetal Acceleration

Answer 10

ac = (v^2) / r

Question 11

Circular Motion: Centripetal Force

Answer 11

Fc = (m v^2) / r

Question 12

Friction (Static and Kinetic)

Answer 12

Ff = u Fn

Question 13

Hooke’s Law

Answer 13

F = -k (xf - xi)

Question 14

Torque

Answer 14

T = F l

Question 15

Kinetic Energy

Answer 15

K = (1/2) m v^2

Question 16

Potential Energy (Gravitational)

Answer 16

Ug = mgh

Question 17

Potential Energy (Spring)

Answer 17

Us = (1/2) k (xf - xi)^2

Question 18

Work (Calculation)

Answer 18

W = F d cos(O)

Question 19

Work (Conservation of Energy)

Answer 19

W = (deltaK) + (delta U) + (delta E internal)

Question 20

Power (given time)

Answer 20

P = (Ef - Ei) / t

Question 21

Power (given force)

Answer 21

P = F v cos(O)

Question 22

Momentum

Answer 22

p = mv

Question 23

What’s the difference between an inelastic and an elastic collision?

Answer 23

In an elastic collision, kinetic energy remains constant. In both, momentum is conserved.

Question 24

Impulse

Answer 24

Favg = (delta p) / (delta t)

Question 25

Energy of a Mass at Rest

Answer 25

E = m c^2

Question 26

Density

Answer 26

p = m / v

Question 27

Pressure (Generally)

Answer 27

P = F / A

Question 28

Pressure (Underwater)

Answer 28

P = p g y

Question 29

Specific Gravity

Answer 29

SG = p(substance) / p(water)

Also = the percentage of an object that will be submerged if placed in water

Question 30

Buoyant Force

Answer 30

Fb = p V g

Question 31

Flow Rate of Fluid

Answer 31

Q = A v

Question 32

Bernoulli’s Equation

Answer 32

Const = P + (1/2) p v^2 + p g h

Question 33

Velocity of Flow Out of Hole (based on depth of water)

Answer 33

v = (2 g h) ^(1/2)

Question 34

Modulus of Elasticity

Answer 34

Mod of Elasticity = stress / strain

Question 35

Velocity of a Wave

Answer 35

v = f (lambda)

Question 36

Period of Wave

Answer 36

T = 1 / f

Question 37

Frequency of a Beat in Sound

Answer 37

fbeat = Abs Val(f1 - f2)

Question 38

Doppler Effect

Answer 38

(delta frequency) / f(source) = v / c

Question 39

Force By One Charge on Another

Answer 39

F = (const q1 q2) / r^2

Question 40

Energy of a Charge

Answer 40

E = const q1 / r^2

Question 41

Potential of a Charge

Answer 41

V = const q1 / r

Question 42

Potential Energy Between Two Charges

Answer 42

U = const q1 q2 / r

Question 43

Voltage of a Resistor

Answer 43

V = iR

Question 44

Power Given Voltage

Answer 44

P = i V

Question 45

Power Given Restance

Answer 45

P = i^2 R

Question 46

Power Given Res + Volt

Answer 46

P = V^2 / R

Question 47

Resistors in Series

Answer 47

R = R1 + R2 +…

Question 48

Resistors in Parallel

Answer 48

1/R = 1/R1 + 1/R2 +…

Question 49

Capacitance

Answer 49

C = Q / V

Question 50

Capacitors in Series

Answer 50

1/C = 1/C1 + 1/C2 +…

Question 51

Capacitors in Parallel

Answer 51

C = C1 + C2 +…

Question 52

Potential Energy of Capacitors

Answer 52

U = (1/2) C V^2

Question 53

Magnetism Force

Answer 53

F = q v B sin(O)

Question 54

Electromagnetic Radiation Speed

Answer 54

c = f (lambda)

Question 55

Energy of a Photon

Answer 55

E = h f

Question 56

Index of Refraction

Answer 56

n = c / v