Units and Measurements

A new unit ( ) of length is chosen such that it is equal to the speed of light in vacuum. What is the distance between Venus and Earth in terms of units if light takes 6 min. 40 s to cover this distance?

1. 200
2. 400
3. 300
4. 500

Consider the equation H= xp qErts Where H = magnetic field intensity; E = electric field, = permittivity, x = distance, t = time The values of p, q, r and s respectively are :

1. 1, 1, 1, 1
2. -1, 1, 2, 1
3. 1, -1, -2, 1
4. -1, -2, -2, 1

The density of a uniform cylinder is determined by measuring its mass m, length l and diameter d. The measured values of m, l and d are 97.42 0.02 g, 8.35 0.05 mm and 20.20 0.02 mm, respectively. Calculated percentage fractional error in is .

1. 0.63%
2. 0.82%
3. 0.72%
4. 0.25%

The potential energy of a particle changes with distance x from a fixed origin as V= A xx+B, where A and B are constants with appropriate dimensions. The dimensions of AB are .

1. [ M1L5/2T-2]
2. [ M3/2L5/2T-2]
3. [ M1L2T-2]
4. [ M1L7/2T-2]

The percentage error in the calculated volume of a sphere, if there is 2% error in its diameter measurement, is .

1. 1
2. 2
3. 6
4. 8

Match List-I with List-II. Choose the correct answer from the options given below :

1. A-I, B-II, C-III, D-IV
2. A-IV, B-III, C-II, D-I
3. A-III, B-IV, C-II, D-I
4. A-II, B-I, C-IV, D-III

In a Vernier calipers, when both jaws touch each other, zero of the Vernier scale is shifted to the right of zero of the main scale and 7th Vernier division coincides with a main scale reading. If the value of 1 main scale division is 1 mm and there are 10 Vernier scale divisions, then the Vernier caliper has

1. 0.07 cm negative zero error
2. 0.7 cm negative zero error
3. 0.07 cm positive zero error
4. 0.7 cm positive zero error

L, C and R represents physical quantities inductance, capacitance and resistance respectively. The dimensional formula M L2 T-4 A-2 corresponds to .

1. R LC
2. RLC
3. C LR
4. 1R LC

Match List-I with List-II. where h (Planck's constant), G (gravitational constant) and c (speed of light in vacuum) as fundamental units. Choose the correct answer from the options given below :

1. A-II, B-IV, C-I, D-III
2. A-IV, B-II, C-I, D-III
3. A-IV, B-I, C-II, D-III
4. A-III, B-I, C-II, D-IV

In an experiment to determine the resistance of a given wire using Ohm's law, the voltmeter and ammeter readings are noted as 10 V and 5 A, respectively. The least counts of voltmeter and ammeter are 500 mV and 200 mA, respectively. The estimated error in the resistance measurement is .

1. 0.25
2. 2
3. 2.5
4. 0.18