According to newtons third law of motion action nd reaction forces are equal in magnitudes nd opposite in direction but they do not cancel each other why ? ?

answer:

the solution:

newton's third law really does say that if a pushes b, then b pushes a with an equal and opposite force. however, these forces do not cancel because they influence the motion of different objects. the force that a exerts on b influences b's motion, and the force that b exerts on a influences a's motion.

scientific laws are the result of testing theories and proving them to be facts.

current flows in a wire