The mass of a pendulum's bob does not affect the period. Newton's second law can be used to explain this phenomenon. In F = m a, force is directly proportional to mass. As mass increases, so does the force on the pendulum, but acceleration remains the same.
The mass of a pendulum's bob does not affect the period. ... As mass increases, so does the force on the pendulum, but acceleration remains the same. (It is due to the effect of gravity.)
