a simple pendulum of period T has a metal bob which is negative charged. if it is allowed to oscillate in a vertically upward uniform vertically ellectric feild its period will be

Answer 1

Period

P = 2*pi*sqrt[(Length)/(Vertical force/Mass)]
= 2*pi*sqrt[L/(M*g*L + q*E)/M]
= 2*pi*sqrt[(L/g) + (L*q*E/M)]
where q is the negative charge and E is the vertical E-field, and M is the bob's mass