In a wheatstone's bridge all the four arms have equal resistance R. If the resistance of the galvanometer arm is also R, the equivalent resistance of the combination as seen by the battery is (a) R/4 (b) R/2 (c) R (d) 2R
In Wheatstone bridge, when the resistance of all the four arms is same , the bridge is balanced.No current will flow through the galvanometer arm. Then ( R+R) will be in parallel to (R+R) ohm The equivalent resistance across the battery is Req = (R+R) × (R+R)/R+R+R+R = R
