Pendulum of unknown length and unknown g, only period given

[mh1985]

Homework Statement

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

Homework Equations

x(t) = A1 cos v_n^t + A2 sin v_n^t?

The Attempt at a Solution

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

 

[mfb]

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.

 

[mh1985]

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.

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

 

[mfb]

That is right, and it will help you.