Answer:
4L
Step-by-step explanation:
Data provided in the question according to the question is as follows
Length = L
Gravity = G
For friend
Length = ?
Growth = 4G
Moreover,
![T_1 = T_2](https://img.qammunity.org/2021/formulas/physics/college/edzmuyla5h6992maypmk73l9hejvela5sg.png)
Based on the above information ,
Now we have to apply the simple pendulum formula which is shown below:
![T = 2\pi (L)/(G)](https://img.qammunity.org/2021/formulas/physics/college/ylq4pgb5wqrwgtduczsc0xi9vb2zzbrwj4.png)
Now equates these equations in both sides
![2\pi (L)/(G) = 2\pi (L)/(4G)](https://img.qammunity.org/2021/formulas/physics/college/htseklzvhmqgo0so8cmqs6fs3f8iv48bng.png)
So after solving this, the length of the pendulum is 4L