Formulas for Physics

Question 1

What are the 3 kinematics formulas?

Answer 1

x(final)=x(initial)+v(initial)t+1/2at^2
v(final)^2=v(initial)^2+2a(delta x)
v(final)=v(initial)+a*t

Question 2

What is the equation for a phase change?

Answer 2

Q=m*l
Q= change in heat
l= specific heat of transformation

Question 3

What is centripetal acceleration?

Answer 3

a=v^2/r

Question 4

What is the formula for weight(W)?

Answer 4

W=mg

Question 5

What is the formula for the force on a wire in a magnetic field?

Answer 5

F= I*L*B*sin theta
F= force on wire
I= current on wire
L= Length of wire
B= external magnetic field
theta= angle between direction of current and magnetic field

Question 6

What is the formula for kinetic energy?

Answer 6

KE=1/2*mv^2

Question 7

Why is delta UE=-W

Answer 7

Because negative work causes KE to decrease which gets converted to UE. (negative work energy theorem means less final KE which)

Question 8

What is the period of a pendulum?

Answer 8

T(pendulum)=2pisqrt(l/g)

l= length of pendulum

Question 9

What is the definition of Pressue?

Answer 9

P=F/A

Question 10

What is Power?

Answer 10

P=W/delta t

Question 11

What is the formula for electric potential?

Answer 11

V=k*q/r

Question 12

What is Hooke’s Law? Which direction does the spring force point?

Answer 12

F(spring)=k(spring constant)*x

Question 13

What is Work Energy Theorem?

Answer 13

W=delta KE

Question 14

What is the equation for a heat engine?

Answer 14

E%=W/Q*100
E=efficiency of the engine
W= work done by engine
Q= heat absorbed by engine

Question 15

What is the electric field generated by two metal plates?

Answer 15

E=V/d

V= voltage of battery

Question 16

What is Newton’s second law?

Answer 16

F=ma

Question 17

Basic Thermo Equation (Hint MCAT)

Answer 17

Q=mc delta T

Question 18

What is Coulomb’s Law?

Answer 18

F=k(q1q2)/r^2

k= a constant

Question 19

What is the equation for momentum?

Answer 19

p=m*v

Question 20

What is total mechanical energy?

Answer 20

E=KE+PE

Question 21

Resistors in series and in parallel?

Answer 21

Series= R1+R2+R3.......
Parallel= 1/R1+1/R2+1/R3.....

Question 22

How do you find electric potential of two charges at distance r?

Answer 22

UE=k(q1q2)/r^2

UE=potential of two charges

Question 23

What is the friction force? (Hint F.U.N equations)

Answer 23

f=u(mu)*normal force (N)

Question 24

What is angular momentum?

Answer 24

L=mvr

Question 25

What is the mirror equation? | What do a positive/negative di and f mean?

Answer 25

1/f=1/do+1/di f= focal length do= distance of object di= distance of image Positive di and f mean real focal length(concave) and real image. Negative di and f mean virtual focal length(convex) and virtual image.

Question 26

What is the wave velocity?

Answer 26

v=(lambda)*frequency | lambda=wavelength

Question 27

What is the wave particle duality?

Answer 27

lambda=h/p lambda= matter wavelength h= a constant p=momentum

Question 28

What is the formula for Work?

Answer 28

W=F*d*cos theta | W= F(parallel to movement)*distance

Question 29

How are frequency and period related?

Answer 29

inversely

Question 30

How do you calculate light going through a medium?

Answer 30

v=c/n | n= index of refraction

Question 31

What is velocity for an object in circular motion?

Answer 31

v=(2*pi*r)/T(period)

Question 32

What are the three power formulas for a circuit?

Answer 32

P=IV P=V^2/R P=I^2*R

Question 33

What is the magnification equation?

Answer 33

m=-(di/do) -m=inverted image |m|>1 means larger image

Question 34

What is the formula for an electric field?

Answer 34

E=k*q/r^2

Question 35

What is the ideal Gas Law?

Answer 35

PV=T

Question 36

What is the formula for potential energy?

Answer 36

PE=mgh

Question 37

What is the period of a spring?

Answer 37

T(spring)=2*pi*sqrt(m/k)

Question 38

What is Newton's Law of Gravitation?

Answer 38

F(g)=G*(m1*m2)/r^2

Question 39

What is impulse?

Answer 39

A change in momentum delta p= p(final)-p(initial) delta p= force*delta t

Question 40

What is the energy of a photon?

Answer 40

E=h*f E= energy of a photon h= a constant f= wave frequency

Question 41

What is the first law of thermodynamics?

Answer 41

delta U= Q-W U= internal energy Q= heat added W= work done by system

Question 42

What is torque?

Answer 42

t=r*f(perpendicular to axis of rotation) | t=r*f*sin theta

Question 43

What is the force on a charge as it moves through an electric field?

Answer 43

F=q*v*B*sin theta | theta= angle between direction of motion and magnetic field

Question 44

What is Snell's Law? Why is it used?

Answer 44

n1 sin theta1=n2 sin theta2 | It is used to calculate the new angle light travels when changing from one medium to another.

Question 45

What is the formula for a potential difference (V)?

Answer 45

delta V= -W/q delta V= delta UE/q W= Work done by E field -W=delta UE

Question 46

What is the force of an electric Field?

Answer 46

F=q*E

Question 47

What is Ohm's Law?

Answer 47

V=IR V= voltage I= current R= Resistance

Question 48

Equation for Capacitance?

Answer 48

q=CV | C is number specific for capacitors like R for resistors

Question 49

What is centripetal force?

Answer 49

F=(m*v^2)/r

Question 50

What is the potential energy for a spring?

Answer 50

PE(spring)=1/2*k*x | x= amount of spring stretch or compression, x=0 is natural spring length