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. If both assertion and reason are true and the reasopn is a true explanation of the assertion
B. If both assertion and reason are true and but the reason is not the correct explanation of assertion
C. If the assertion is true but reason is false
D. If both the assertion and reason are false

Answer

C

Explanation

Amplitude of oscillation for a forced , damped oscillation is `A = (F_(0)//m)/(sqrt((omega^(2) - omega_(0)^(2)) + (b omega//m)^(2)))` where `b` is constant released to the strength of the resistive force `omega_(2) = sqrt(k//m)` is nature frequency of undamped oscillation `(b = 0)` When the frequency of driving force `(omega) = omega_(2)` then amplitude `A` is very larger
For `omega = omega_(0) or omega gt omega_(2)` the amplitude decreases.