Laws of Motion Flashcards
1
Q
Momentum P =
A
√2mKE
2
Q
Impulse J =
A
change in momentum = Fdt
3
Q
Area under Ft gives
A
impulse
4
Q
Recoil of gun Vr
A
Vr = -mV/M
5
Q
Speed Vr =
A
mV/M
6
Q
F in recoil of gun
A
nmV
7
Q
For a connected system of 2 masses, a =
A
(m1-m2)g/m1+m2
8
Q
For a connected system of 2 masses, a =
A
2m1m2g/m1+m2
9
Q
Motion along inclined surface V =
A
√2gLsinθ L = len of inclined surf
= √2gH
10
Q
Motion along inclined surface, time to reach ground t =
A
√2L/a = 1/sinθ√2H/g
11
Q
μk <
A
μs
12
Q
Motion in circular path
A
Vmax = √(μ(s) rg)
13
Q
W by spring force
A
Ws = -kx^2/2
14
Q
W by static fric =
A
0
15
Q
W by kinetic fric =
A
-μmgS
16
Q
KE =
A
PV/2
17
Q
Work energy theorem
A
W = change in KE
18
Q
stopping dist
A
S = mu^2/2F
19
Q
W against conservative force
A
ΔPE
20
Q
W by conservative force
A
-ΔPE
21
Q
W by centripetal force
A
0
22
Q
1 horsepower =
A
746W
23
Q
Wt graph gives
A
P
24
Q
Efficiency η =
A
(O/P) power/(I/P) power
25
When P = 0, V =
√2Pt/m
26
When P = 0, a =
√P/2mt
27
Elastic collision
Linear mom, KE conserved, bodies regain shape, force must be conservative
28
Inelastic collisoin
L.M conserved, KE not conserved, bodies don't regain shape, some f may not be conservative
29
Perfectly inelastic collision
LM conserved, KE not conserved, body is well deformed & don't regain shape, All F is not conservative
30
If coeff of restitution = 0,
perfect inelastic
31
If coeff of restituion = 1
Perfect elastic
32
If coeff btn 0 & 1
partial inelastic
33
For perfect elastic,
V1 = [(m1-m2)u1 + 2m2u2]/m1+m2
34
For perfect inelastic
V = [m1u1 + m2u2]/m1+m2
35
KE loss =
m1m2(u1-u2)^2/2(m1+m2)
36
When u1 & u2 are opp, KE loss =
m1m2(u1+u2)^2/2(m1+m2)
37
r =
(m1r1 + m2r2)/m1+m2
38
Center of mass for cone
Solid cone - h/4
Hollow cone - h/3
39
In explosion in parabolic path
m1r1 = m2r2
40
Shift in trolley in opp dir
x = ml/m+M
41
Radius of gyration K for ring =
MR^2
42
K for disc
MR^2/2
43
K for solid sphere
2/5MR^2
44
K for hollow sphere =
2/3MR^2
45
K for rod
ml^2/12
46
Moment of inertia I =
mr^2
47
Angular momentum L =
Iω
48
Angular impulse
ΔL
49
Rotational power Pr =
τω
50
KE of pure rolling body
1/2mv^2 β
51
V for Rolling motion on an inclined plane
V = √2gH/β
52
a for rolling motion on inclined plane
a = gsinθ/β
53
t for rolling motion on inclined plane
t = 1/sinθ√2hβ/g
