A small sphere of mass `m = 0.5 kg` carrying a positive charge `q = 110 mu C` is connected with a light, flexible, and inextensible string of length of length `r = 60 cm` and whirled in a vertical circle. If a vertically upward electric field of strength `E = 10^5 NC^-1` exists in the space, calculate the minimum velocity of the sphere required at the highest point so that it may just complete the circle `(g = 10 ms^-2)`.

A small sphere of mass m = 0.6 kg carrying a positive charge q = 80 muC is connected with a light, flexible, and inextensible string of length r = 30 cm and whirled in a vertical circle. If a horizontal rightward electric field of strength E = 10^5 NC^-1 exists in the space, calculate the minimum velocity of the sphere required at the highest point so that it may just complete the circle (g = 10 ms^-2) .

Two small particles A and B having masses m = 0.5 kg each and charges q_1 = (-155//18 muC) and q_2 = (+100 muC) , respectively, are connected at the ends of a nonconducting, flexible, and inextensible string of length r = 0.5 m . Particle A is fixed and B is whirled along a verticle circle with center at A. if a vertically ipward electric field of Strength E = 1.1 xx 10^5 NC^-1 exists in the space, calculate the minimum velocity of particle B required at the highest point so that it may just complete the circle (g = 10 ms^-2) . .

A stone is whirled in a vertical circle at the end of a rope of length 0.5m . The velocities of the stone at lowest and highest points to just complete the circle are [Take ,g =9.8ms^(-2)]

A small sphere of mass m and carrying a charge q is attached to one end of an insulating thread of length a, the other end of which is fixed at (0,0) as showing in figure. There exists a uniform electric field vecE=-vecE_0hatj in the region. The minimum velocity which should be given to the sphere at (a, 0) in the direction shown so that it is able to complete the circle around the origin is (There is no gravity)

A stone of mass 1kg tied to a light inextensible sstring of length L=10m is whirling in a circular path of radius L in vertical plane. If the ratio of the maximum tension in the string to the minimmum tension in the string is 4 and if g is taken to be 10ms^(-2) , the speed of the stone at the highest point of the circle is.

A stone of mass 100 g attached to a string of length 50 cm is whirled in a vertical circle by giving it a velocity of 7 m/s at the lowest point. Find the velocity at the highest point .