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NEETPhysicsUnits and Dimensions

Assertion (A): Special functions such as trigonometric, logarithmic and exponential functions are not dimensionless. Reason (R): A pure number, ratio of similar physical quantities, such as angle and refractive index, has no dimensions.

Options

  1. AAssertion (A) is true, Reason (R) is true; Reason (R) is a correct explanation for Assertion (A).
  2. BAssertion (A) is true, Reason (R) is true; Reason (R) is not a correct explanation for Assertion (A).
  3. CAssertion (A) is true, Reason (R) is false.
  4. DAssertion (A) is false, Reason (R) is true.

Correct answer

D. Assertion (A) is false, Reason (R) is true.

Step-by-step solution

The arguments of special functions, such as the trigonometric, logarithmic and exponential functions must be dimensionless. A pure number, ratio of similar physical quantities, such as angle as the ratio (length/length), refractive index as the ratio of (speed of light in vacuum/speed of light in medium), etc. has no dimensions.

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