Homework Help: Amplitude & Time constant

1. Feb 7, 2010

LBRRIT2390

1. The problem statement, all variables and given/known data

A gust of wind hits a flagpole and starts it oscillating. After 10 s, the amplitude of its motion has decreased to 25% of its initial value.

What is the value of the time constant?

2. Relevant equations

xmax(t) = Ae$$-t/\tau$$

3. The attempt at a solution

I know that the answer is 7.2s, but how do I find it?

How do I manipulate the above equation?

2. Feb 8, 2010

willem2

Use the equation you gave at with t=0 and also with t=10