In the Previous Problem, If the Mass Is Set in Motion

Multiple Choice

In the previous problem, if the mass is set in motion, the natural frequency, $\omega$ , is

A) $2 \mathrm { sec }$
B) $2 \sec ^ { - 1 }$
C) $4 \mathrm { sec }$
D) $4 \sec ^ { - 1 }$
E) $16 \mathrm { sec } ^ { - 1 }$