# The time that a swing takes to move from forward and backward can be determined by the formula T=2(PI) square root of L divided by 9.8`` "T" is the time (s) "l" is the length of the rope...

The time that a swing takes to move from forward and backward can be determined by the formula T=2(PI) square root of L divided by 9.8``

"T" is the time (s) "l" is the length of the rope that supports the swing in meters.

Determine the length of the rope for a swing that takes 3.4 seconds to move from the front to the rear. Round to the nearest tenth

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### 1 Answer

`T = (2pi)sqrt(L/g)`

`T^2 = 4pi^2xxL/g`

`L = (T^2g)/(4pi^2)`

When T = 3.4

`L = (3.4^2xx9.8)/(4xxpi^2)`

`L = 2.8696m`

`L = 2.9m`

*So the required length of the rope is 2.9m.*