Question

The equation of motion for a spring -mass system excited by a harmonic force is $M\ddot{x}+kx=Fcos\left(\omega t\right)$
where M is the mass, k is the spring stiffness, F is the force amplitude and $\omega$ is the angular frequency of excitation. Resonance occurs when $\omega$ is equal to

• A. $\sqrt{\frac{2k}{m}}$
• B. $\frac{1}{2\pi }\sqrt{\frac{2k}{m}}$
• C. $2\pi \sqrt{\frac{k}{m}}$
• D. $\sqrt{\frac{k}{m}}$

Answer 1

The correct option is D $\sqrt{\frac{k}{m}}$

$\sqrt{\frac{k}{m}}$