問題詳情
12.A block with mass m
250g is fastened to a spring with spring constant k
85N/m. The system is excited tooscillate. Assume that there is a velocity-dependent damping force Fd
-bv in the system with b
70g/s.How long does it take for the amplitude of the damped oscillation to drop to half its initial value? (ln2
0.693)
(A)3s
(B)4s
(C)5s
(D)6s
(E)7s
參考答案