PHY 315 Midterm Exam 1
Show your work. Hand in your formula sheet along with your solutions.
1) (30 pts.) An LC circuit starts oscillating at t= 0, at which point the current through the
inductor has its maximal value of I= 0.1 A. At t= 0.3 ms the capacitor is releasing energy at one half
its maximal power P=−
1
2Pmax for the first time. Find the maximum charge on the capacitor.
2) (30 pts.) The period of a damped oscillator increases by one percent when its damping coefficient
νis doubled. If this oscillator (with the original damping coefficient) is driven at ω= 1.05 ω0, by what
factor (ˆx/ ˆ
X) is the driving amplitude enhanced?
3) (40 pts.) For the system shown below, find the value of k′such that ω2= 7k/m is a normal
frequency.
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2m
mk02k
k