JEE PHYSICS MCQ: UNITS & MEASUREMENTS

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Analyzing +4 | -1

If a book with many printing errors contains four different formulae for the displacement

y

of a particle undergoing a certain periodic motion.
(1)

y=a \sin \frac{2 \pi t}{T}

(2)

y=a \sin v T

(3)

y=\frac{a}{T} \sin \frac{t}{a}

(4)

y=(a \sqrt{2})\left(\sin \frac{2 \pi t}{T}+\cos \frac{2 \pi t}{T}\right)

where

a

is the maximum displacement of the particle,

v

is the speed of particle,

T

is the time period of motion. Then dimensionally

View answer and explanation

Correct option: B

(2) and (3) are wrong

Option B is correct because formulas (2) and (3) are dimensionally incorrect. The arguments of trigonometric functions must be dimensionless, and the dimensions of y must be length.

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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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