# Pendulum of unknown length and unknown g, only period given

1. Sep 27, 2012

### mh1985

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

Pendulum of unknown length, l, has period of 9.32 seconds. Length is increased by 1 metre, and time period increases to 9.734 seconds. Calculate original length of pendulum and determine whether the experiment was conducted on earth. Hint: g is not assumed to be 9.81 ms^-2, you must find both g & l

2. Relevant equations

x(t) = A1 cos vnt + A2 sin vnt?

3. The attempt at a solution

Really not sure where to start, due to the two unknowns!

2. Sep 27, 2012

### Staff: Mentor

Can you express the period as function of g and l?
For both pendulum lengths, you get an equation, so you have two unknowns and two equations.

3. Sep 27, 2012

### mh1985

T=2pi(sqrt(l/g) ?

4. Sep 28, 2012