need ur help in physics HW..plzzzzzzzz?

Question

A simple pendulum has a period of 2.5 s.
what is its lenght?
what would be its period on the moon, where g(moon)= 1.67 m/s2

Answer 1

period is 2 pi times square root of length divided by g:
http://en.wikipedia.org/wiki/Pendulum

Answer 2

T=period
l=length
g=gravity
3.14.......=pi
sqrt=square root

T=2pi*sqrt(l/g)

T/2pi=sqrt(l/g)

(T/2pi)^(2)=l/g

l=g((T/2pi)^(2))

l=(9.81)((2.5/2pi)^(2))
=(9.81m/s^2)(15.42s^2)
=151.27m
(sig digs)=
1.5*10^2m


Now that you know the length of the rope you know it will remain a constant because whether the rope be on earth or the moon it will not change length
------------------------------------------------------------------------------------
T=2pi*sqrt(l/g)
=2pi*sqrt(151.3/1.67m^s2)
=2pi*9.52s
=59.8s
sig digs
=6.0*10^1s

this is the tension on the moon of the rope