Hello Aspirant

I hope you are doing good.

I would like to tell you that this question can easily be solved with free body diagram

After making Free body diagram you will observe that tension applied on the string is equal to graviattional force applied on it

so by equating the two forces

Denoting tension by T

T=mass of block *g

= 10*10

that will be 100 newton

Hope you found this answer helpful. Good luck for your future