Person connects four cells in series but one cell has its terminal reversed. the internal resistance is 0.25 Ohm. If Each cell has an emf of 1.5 V the current flowing is? - a) 1 A b) 2.5 A c) 1.5 A d) zero

1 Answer
Feb 14, 2018

Here 4 cells each having emf #e=1.5V# and internal resistance #r=0.25Omega# are connected in series. So total resistance of the circcuit will be #4*r=4*0.25=1Omega#

As one of the cell is connected in reverse direction the effective emf becomes #E=3*e-e=2e=2*1.5=3V#

Hence current in the circuit

#I="net emf"/"total resistance"#

#=3/1=3A#