Units and Measurement

A body is moving at a speed near 0.3 ms^-1. To measure its speed with an accuracy about 1%, using a sampling distance 3 mm, the measuring clock should have a least count of the order of

• 0.1 s

• 0.01 s

• 0.001 s

• 0.0001 s

The dimensions of $\frac{\mathrm{a}}{\mathrm{b}}$ in the equation $\mathrm{p} = \frac{\mathrm{a} - {\mathrm{t}}^2}{\mathrm{bx}}$where, p is pressure, x is distance and and t is time, are

• [M²LT^-3]

• [MT^-2]

• [LT^-3]

• [ML³T^-1]

The dimensional formula for inductance is

• [ML²T^-2A^-2]

• [ML²TA^-2]

• [ML²T^-1A^-2]

• [ML²T^-2A^-1]

The physical quantity having the same dimensions as Planck's constant h is

• linear momentum

• angular momentum

• Boltzmann constant

• force

SI unit of permittivity is

• C²m²N²

• C²m^-2N^-1

• C²m²N^-1

• C^-1m²N^-2

Out of the following four dimensional quantities, which one qualifies to be called a dimensional constant ?

• Acceleration due to gravity

• Surface tension of water

• Weight of a standard kilogram mass

• The velocity of light in vacuum

The physical quantity having the dimensions [M^-1L^-3T³A²] is

• resistance

• resistivity

• electrical conductivity

• electromotive force

The dimensional formula for impulse is

• [MLT^-1]

• [ML^-1T]

• [M^-1LT^-1]

• [ML^-1T^-1]

Dimensional formula for the universal gravitational constant G is

• [M^-1L²T^-2]

• [M⁰L⁰T⁰]

• [M^-1L³T^-2]

• [M^-1L³T^-1]

The number of significant figures in the numbers 4.8000 x 10⁴ and 48000.50 are respectively

• 5 and 6

• 5 and 7

• 2 and 7

• 2 and 6