Identify the pair whose dimensions are equal.
The dimensions of torque and work are [ML2T-2]
The physical quantities not having same dimensions are
Planck's constant (in term of unit)
(h) = j-s
Momentum (p) = kg-ms-1
=[M][L][T-1] = [MLT-1]
Dimensions of where symbols have their usual meaning, are
As we know that formula of velocity is
Which one of the following represents the correct dimensions of the coefficient of viscosity?
By Newton's formula
Out of the following pairs, which one does not have identical dimensions ?
I = mr2
∴[I] = [ML2]
and = moment of force =
∴ = [L][MT-2]=[ML2T-2]
The 'rad' is the correct unit used to report the measurement of
'rad' is used to measure biological effect of radiation.
Which of the following units denotes the dimensions [ML2/Q2], where Q denotes the electric charges ?
[L→ inductance, i → current]
Energy has the dimension = [ML2T-2]
Equate the dimension, we have
A body of mass m = 3.513 kg is moving along the x-axis with a speed of 5.00 ms-1. The magnitude of its momentum is recorded as
m = 3.513 kg and v = 5.00 ms-1
So momentum, p = mv = 17.565 As the number of significant digits in m is 4 and in v is 3, so p must have 3 (minimum) significant digits.
Hence, p = 17.6 kg ms-1
The dimensions of magnetic field in M, L, T and C (coulomb) is given as
In an experiment the angles are required to be measured using an instrument. 29 divisions of the main scale exactly coincide with the 30 divisions of the vernier scale. If the smallest division of the main scale is half-a-degree (= 0.5°), then the least count of the instrument is
The respective number of significant figures for the numbers 23.023, 0.0003 and 2.1 × 10–3 are
(i) All the non-zero digits are significant.
(ii) All the zeros between two non-zero digits are significant, no matter where the decimal point is, if at all.
(iii) If the number is less than 1, the zero(s) on the right of decimal point but to the left of the first non-zero digit are not significant.
(iv) The power of 10 is irrelevant to the determination of significant figures. According to the above rules, 23.023 has 5 significant figures. 0.0003 has 1 significant figures. 2.1 × 10–3 has 2 significant figures.