If the length of a pendulum is doubled what will be the change in its time period?

If the length is doubled, the period will increase by a factor of √2 .

Explanation:

For Simple Pendulum

T = 2π√(L/g) (1)

Where T is time period, L is length and g is acceleration due to gravity

Now,

If we double the length,

T = 2π√2L/g

T = √2(2π√(L/g)

From (1), We get

T = √2(T)

So,

If the length is doubled, the period will increase by a factor of √2 .

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