PHYS101 FORMULA SHEET for Module 1
I RING = MR 2 (Thin ring)
DYNAMICS
1st Condition of Equilibrium:
Fx = 0
Fy = 0
Fz = 0
nd
Newton’s 2 Law of Motion:
a=
Friction Force:
ELASTIC COLLISION:
m1v1 + m2v2 = m1u 1 + m2u 2
COEFFICIENT OF RESTITUTION:
Fnet
m
e=
f k = k N
fs = s N
WORK, POWER, and ENERGY
Work: W = Fd cos 
u2 − u1
v1 − v2
Angular Displacement: s = r
Kinetic Energy: K = 12 mv 2

t
v = r
Work-Energy Theorem:
W = K = 12 mv 2 − 12 mvo 2
Angular Acceleration  ave
W = K + U + W f
1
M  R12 + R22 
2 
I ROD =
1
ML2 (Axis at center)
12
1
I ROD = ML2 (Axis at end)
3
ANGULAR QUANTITIES
Angular Velocity: ave =
I RING =

=
t
I SPHERE =
2
MR 2 (solid)
5
I HOLLOW =
2
MR 2
3
TORQUE:
 = rF sin 
 = I
a = r
Work Done by Spring Force:
Ws = 12 kxo 2 − 12 kx 2
ROTATIONAL KINEMATICS:
Power: P = Fvave
Pavg
=
W
=
t
 2 − o 2
 =
2
U ( y ) = mgy
U ( x) =
1 2
kx
2
IMPULSE and MOMENTUM
Impulse and Change in Momentum:
t
Rotational Kinetic Energy:
K=
1 2
I
2
Total Kinetic Energy:
K=
1
1
mvcm 2 + I  2
2
2
Ft = mv − mvo
Conservation of Momentum:
EXPLOSION:
−m1v1 = m2 v2
INELASTIC COLLISION:
m1v1 + m2v2 = ( m1 + m2 ) v
 x = 0
 y = 0
 z = 0
 clockwise =  counter −clockwise
 = o t + 12  t 2
Gravitational Potential Energy:
Elastic Potential Energy:
 − o
2nd Condition of Equilibrium:
MOMENT OF INERTIA:
I particle = mr 2
I DISK =
1
MR 2
2
Work in Rotational Motion:
W =  
Power in Rotational Motion:
P =  av
Angular Momentum: L = I 
Conservation of Angular Momentum:
I11 = I 22