question_answer 8)

Two point charges and are located 20 cm apart in vacuum.                 (a) What is the electric field at the midpoint O of the line AB joining the two charges?                 (b) If a negative test charge of magnitude is placed at this point, what is the force experienced by the test charge?  

Answer:

(a) Electric field at the mid point of the separation between two equal and opposite charges is given by                 i.e.             [Here]                 i.e.                 along OB.                 (b)Force experienced by test charge due to charge