A simple pendulum with length L and mass m of the bob is oscillating with an amplitude A. The maximum tension in the string is
mg
mg1+AL2
mg1+A2L2
T−mgcosθ=mv2LT is maximum when θ=0,Tmax−mg=mvmax2LTmax=mg+mω2A2L=mg+mgA2L2∵ω2=gLTmax=mg1+A2L2