Which two of the following five physical parameters have the same dimensions?
1) Energy density
2) refractive index
3) dielectric constant
4) Young's modulus
5) Magnetic field
2 and 4
3 and 5
1 and 4
1 and 4
Dimensions of resistance in an electrical circuit, in terms of the dimension of mass M, of length L, of time T and of current I, would be:
[ML2T-3I-1]
[ML2T-2]
[ML2T-1I-1]
[ML2T-1I-1]
The velocity v of a particle at time t is given by where a, b and c are constants, The dimensions of a, b and c are respectively:
The physical quantity of the dimensions of length that can be formed out of c, G and e/4πε0 is [c is the velocity of light, G is the universal constant of gravitation and e is charge]
A student measured the diameter of a small steel ball using a screw gauge of least count 0.001 cm. The main scale reading is 5 mm and zero of circular scale division coincides with 25 divisions above the reference level. If screw gauge has a zero error of –0.004 cm, the correct diameter of the ball is
0.521 cm
0.525 cm
0.529 cm
0.053
C.
0.529 cm
Diameter of the ball
= MSR + CSR x (least count) - zero error
= 0.5 cm + 25 x 0.001 - (-0.004)
= 0.5 + 0.025 + 0.004
= 0.529 cm
The length, breadth and thickness of a block are given by l = 12 cm, b = 6 cm and t = 2.45 cm. The volume of the block according to the idea of significant figures should be
1 × 102 cm3
2 × 102 cm3
1.76 × 102 cm3
None of these
In a system of units if force (F), acceleration (A), and time (T) are taken as fundamental units, then the dimensional formula of energy is:
FA2T
FAT2
F2AT
FAT
Dimensions of resistance in an electrical circuit, in terms of dimension of mass M, of length L, of time T and of current I, would be
[ M L2 T-3 I-1]
[M L2 T-1]
[M L2 T-1 I-1]
[M L2 T-3 I-2 ]
The physical quantity having the dimensions [ M-1 L-3 T3 A2 ] is
resistance
resistivity
electrical conductivity
electromotive force