Question

The drawing shows an equilateral triangle, each side of which has a length of 3.36 cm. Point charges are fixed to each corner, as shown. The 4.00 C charge experiences a net force due to the charges qA and qB. This net force points vertically downward and has a magnitude of 761 N. Determine (a) charge qA, (b) charge qB.

Answer 1

Since resultant force direction is vertically downward

So resultant force in horizontal direction should be zero. It is only possible when qA and qB should be equal and negative in nature.

a). qA=-13.78×10^(-12) C= 13.78 pC

b). qB = -13.78pC. Using equation 2 .here. p=10^(-12)