Posted by **Gabi** on Monday, April 11, 2011 at 3:15am.

The formula T=2*pi*sqrt[L/32] gives the period of a pendulum of length l feet. The period P is the number of seconds it takes for the pendulum to swing back and forth once. Suppose we want a pendulum to complete three periods in 2 seconds. How long should the pendulum be? Thank you so much for helping. The solution must be sbout 0.36 ft. I tried everything but I'm still wrong. Thanks again!!!!

- math -
**drwls**, Monday, April 11, 2011 at 4:56am
To complete three periods in 2 seconds, the period must be

T = 2/3 = 0.6667 s

I will use your formula although physics says that the denominator in the sqrt[L/32] should be 32.2 ft/s^2, not 32. That is the value of g, the acceleration due to gravity.

Anyway, using 0.6667 = 2*pi*sqrt(L/32),

sqrt(L/32) = 0.10611

L/32 = (0.10611)^2 = 0.01127

L = 0.3603 feet

With the correct formula,

L/32.2 = (0.10611)^2

L = 0.3625 ft

## Answer this Question

## Related Questions

math - The formula T=2*pi*sqrt[L/g] gives the period of a pendulum of length l ...

Math - The formula l=8t^2/pi^2 represents the swing of a pendulum. In this ...

math 209 - the time t for a pendulum to swing back and forth once is called its ...

algebra - The period of a pendulum is the time it takes to swing from left to ...

math - The period of a pendulum can be found by using the formula,where L is ...

Math - Linear Equations - "the period of a pendulum, T (in seconds) varies ...

College Algebra - The period (the time required for one complete swing) of a ...

algebra - The period t ( in seconds) of a simple pendulum as a function of its ...

Physics - In a labratory experiment, a student measured the period of a swing ...

Pre-Calculus - The Period T, in seconds, of a pendulum depends on the distance...