Units & Dimensions Flashcards
1
Q
Representation of physical quantities
A
PQ=nU
2
Q
Graph of n and U
A
Rectangular Hyperbole
3
Q
Changimg Unit & magnitude to another
A
n1U1 = n2U2
4
Q
7 Fundamentals quantities
A
Length
Mass
Time
Temperature
Amount of substance
Luminous Intensity
Electric current
5
Q
Unit of fundamental quantities
A
M
Kg
S
K
Mol
λ
A
6
Q
Supplimentary quantities
A
Plane angle
Solid angle
7
Q
Unit of supplimentary quantities
A
Rad
Strad
8
Q
MKS system of units
A
Meter–Kilogram–Second
9
Q
CGS System of Units
A
Centimeter–Gram–Second
10
Q
FPS System
A
Feet–Pound–Second
11
Q
1⁰
A
1.75×10–2rad
12
Q
1’
A
2.91×10–4 rad
13
Q
1’’
A
4.85×10–5 rad
14
Q
Plane angle =
A
Arc/radius
15
Q
Solid angle =
A
Area/radius²
16
Q
Device Used for parallax
A
Sextant
17
Q
Angle in measurement of parallax
A
θ=b/r
18
Q
Distance to a planet
A
r=b/θ
r–distance to the planet
b–distance btw 2 observatories
19
Q
Diameter of a planet
A
d=ΦD
d–diameter of planet
D–distance to the planet
20
Q
1 amu =
A
1.66×10–27
21
Q
Mass of 1 e
A
9.1–31 kg
22
Q
Quintel
A
100kg
23
Q
Tonne
A
1000kg
24
Q
Time span of an unstable particle
A
10–24s
25
Uncertainty of cesium clock
•1in10-13s
•3μs
26
1AU (Astronomical unit)
1.496×10¹¹m
27
1ly (light year)
9.46×10¹⁸m
28
1 parsec
3.08×10¹⁶
29
Size of a proton
10-15m
30
Radius of earth
10⁷
31
1angstrom Å
10–10
32
Mass using G,h&c
M=√(hc/G)
33
h
Planks constant
34
G
Gravitational constant
35
C
Speed of light
36
Length using G,h&c
L=√(hG/c³)
37
Time using G,h&c
T=√(hG/c⁵)
38
D❗√(l/g)
T
39
D❗√(m/k)
T
k–spring constant
40
D❗√(R/g)
T
R–radius of earth
41
D❗L/R
T
L–inductance
C–capacitance
42
D❗RC
T
R–resistance
43
D❗√(LC)
T
44
D❗f
T–1
45
D❗R/L
T-1
46
D❗1/RC
T–1
47
D❗1/√(LC)
T–1
48
D❗angular velocity (ω)
T–1
49
D❗Velocity gradient
T-1
50
D❗Energy density (1/2E²ε)
ML–1T–2
51
D❗Pressure
ML–1T–2
52
D❗Stress
ML–1T–2
53
D❗Rigidity modulus
ML–1T–2
54
D❗Young's Modulus
ML–1T–2
55
D❗Bulk Modulus
ML–1T–2
56
D❗Momentum (p)
MLT–1
57
D❗Impulse
MLT–1
58
D❗Thrust
MLT–2
59
D❗Force
MLT–2
60
D❗Tention
MLT–2
61
D❗Weight
MLT–2
62
D❗Moment of Inertia
ML²T–2
63
D❗Energy stored in a capacitor
ML²T–2
64
D❗Energy
ML²T–2
65
D❗Torque
ML²T–2
66
D❗Work
ML²T–2
67
D❗Angular momentum (l)
ML²T–1
68
D❗Plank's constant
ML²T–1
69
D❗Angular Impulse
ML²T–1
70
D❗Acceleration
LT–2
71
D❗Intesity of Gravitational Field
LT–2
72
D❗Latant Heat
L²T–2
73
D❗Gravitational Potential
L²T–2
74
D❗Thermal Capacity
ML²T–2K–1
75
D❗Boltzmann Constant
ML²T–2K–1
76
D❗Entropy
ML²T–2K–1
77
D❗Universal Gas Constant
ML²T–2K–1
78
D❗Angle
Dimensionless
Has Unit
79
D❗Solid Angle
Dimensionless
Has Unit
80
D❗Strain
Dimensionless
81
D❗Refractive Index
Dimensionless
82
D❗Relative Density
Dimensionless
83
D❗Poisson's ratio
Dimensionless
84
D❗Specific Gravity
Dimensionless
85
D❗Relative Error
Dimensionless
86
D❗Mass Fraction
Dimensionless
87
D❗Mole Fraction
Dimensionless
88
1km/h
5/18 ms–1
89
1 Calorie
4.2 J
90
1 Newton
10⁵ dyne
91
1 HP
746 W
92
1 KWH
36×10⁵ J
93
1 Weber
10⁸ Maxwell
94
1 Joule
10 erg
95
1 eV
1.6×10–19
96
1 litre
10³ m³
97
1 Tesla
10⁴ Gauss
98
1 Kg wt
9.8 N
99
X⁰C
X+273 K
100
D❗Trigonometric value
(Trigno) x = 1
101
D❗Exponential
e^xy = 1
102
Accuracy
It is the closeness to the true value
103
Precision
Linit to which a qantity is measured to
determined by least count
104
Smallest least count
Greatest precision
105
Error =
Measured value — True Value
106
amean=
(a1 + a2 + .......an)/n
107
Absolute error =
Δa1= |a1- amean |
Δa2 = |a2- amean|
108
Mean absolute error =
Δamean = (Δa1 + a2.....Δan)/n
109
Relative/Fractional error =
(Δamean)/amean
110
Percetange fractional/Fractional error
(Δamean)/amean ×100
111
If uncertain digit is < 5
The digit next to the uncertain digit remains the same
112
If uncertain digit is > 5
The digit next to the uncertain digit is increased by 1
113
If uncertain digit is = 5
■If the next digit is odd then we add it by +1
■If the next digit is even then it remains the same
114
Errir in case of addition
(a±Δa) + (b±Δb) = a+b (Δa±Δb)
115
Error in case of difference
(a±Δa) – (b±Δb) = a–b (Δa±Δb)
116
Error in case of multiplication
A×B=R
ΔR/R = ΔA/A + ΔB/B
117
Error in case of division
A/B=R
ΔR/R = ΔA/A + ΔB/B
118
Error in case of exponents
Z=an
ΔZ/Z = n(ΔA/A)
119
True reading
Observed reading – 0error
120
Measuring instruments in the order of hightest—Lowest least count
Meter Scale
Vernier Scale
Screw Gauge
121
📏Relation btw MSD & VSD
(9/10)MSD=1VSD
122
📏Total Reading =
Main Scale + Coinciding Division × Least Count
123
🗜 No error
When 0 of the main scale COINSIDE with 0 of vernier scale
124
🗜 +ve 0 error
When 0 of main scale is to the RIGHT of the vernier scale
125
🗜 –ve 0 error
When 0 of the main scale is to the LEFT of the vernier scale
126
🔩 Pitch =
Displacement of screw / No of rotations
127
🔩 Least Count =
= Pitch / No of division of circular scale
128
🗜 Total Reading =
Path Scale reading + (correction hand scale division × least count)
129
🗜 0 Error =
Least Count × No by which 0 is displaced in circular scale
130
🗜 True Reading =
Observed Reading – 0Error
131
√(E0/B0 =
C
132
√(μ0/ε0 =
R
133
Deca (de)
101
134
Hecto (h)
102
135
Kilo (k)
103
136
Mega (M)
106
137
Giga (G)
109
138
Tera (T)
1012
139
Deci (d)
10–1
140
Centi (c)
10–2
141
Milli (m)
10-3
142
Micro (μ)
10-6
143
Nano (n)
10-9
144
Pico (p)
10-12
