Assertion : Resonance is special case of force vibration in which the nature frequency of vebration of the body is the same as the impressed frequency of external periodic force and the amplitude of force vibration is maximum
Reason: The amplitude of forced vibrations of a bodyincrease with an increase in the frequency of the externally impressed perioic force

Options

A. Assertion is correct, reason is correct, reason is a correct explanation for assertion.
B. Assertion is correct, reason is correct, reason is not a correct explanation for assertion
C. Assertion is correct, reason is incorrect
D. Assertion is incorrect, reason is correct

Answer

C

Explanation

Amplitude of oscillation for a forced damped oscillatory is `A = (F_(0)//m)/(sqrt((omega^(2)-omega_(2)^(2))+(bomega//m^(2))))` where b is constant related to the strength of the resistive force, `omega_(0) = sqrt(K//m)`
is natural frequency of undamped oscillor (b=0)
When the frequnecy of diving force `(omega) ~~ omega_(0)` then amplitude A is very larger.
For `omega lt omega_(6) ` or `omega lt omega_(0)` , the amplitude decrease.