when we half the length of simple pendulum what will be its time period?plz reply
This is something that is hard to tell you without doing the problem for you.
Since you are not given actual values, you have to use variables.
You are told that L1/L2=2 (L2 is half of L1), you need to find T1/T2, you know the formula that relates the period of a pendulum to it's length.
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