JEE PHYSICS MCQ: UNITS & MEASUREMENTS

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A spherometer has 100 equal divisions marked along the periphery of its disc and one full rotation of the disc advances on the main scale by

0.01 \mathrm{~cm}

. The least count of this system is

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Correct option: B

10^{-4} \mathrm{~cm}

Option B is correct because the least count of a spherometer is calculated by dividing the pitch by the number of divisions on the circular scale, which in this case is 0.01 cm / 100 = 10^-4 cm.

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\mathrm{ms}^{-1} \text {. }

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\frac{1}{\left(\sqrt{\varepsilon_0 \mu_0}\right) t} \text {. }

The method of dimensional analysis can be used to derive which of the following relations? Statement-I: Dimensions of constant of proportionality of constants can be derived from dimensional method
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\left[ {{\mathrm{M}^{ - 1}}{\mathrm{L}^{ - 3}}{\mathrm{A}^2}{T^3}} \right]

is A quantity X is given by

{\varepsilon _0}L\frac{{\Delta V}}{{\Delta t}},\;

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{\varepsilon _0}

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{\Delta V}

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{\Delta t}

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