It takes 20.0 s for a exponentially damped harmonic oscillator to ...

[Frost2351]

It takes 20.0 s for a exponentially damped harmonic oscillator to have its amplitude decrease from its initial value to one-half the initial value.
 
  How long does it take the amplitude to decrease from its initial value to one-fourth the initial value?
  A)
 
  40.0 s
 
  B)
 
  60.0 s
 
  C)
 
  50.0 s
 
  D)
 
  80.0 s
 
  E)
 
  30.0 s

Question 2

In a lab experiment, a student brings up the rotational speed of a rotational motion apparatus to 30.0 rpm. She then allows the apparatus to slow down on its own, and counts 240 revolutions before the apparatus comes to a stop.
 
  The moment of inertia of the flywheel is 0.0850 kgm2. What is the retarding torque on the flywheel? A)
 
  0.0425 Nm
  B)
 
  0.159 Nm
  C)
 
  0.0787Nm
  D)
 
  0.000278 Nm
  E)
 
  0.0000136 Nm

[matt]

Answer to Question 1

A

Answer to Question 2

D

[Frost2351]

Gracias!

[kjohnson]

Excellent