Question

20 identical cells are connected in series with a load of resistance and current in it is ( I ) now polarity of some cell are reversed then current becomes( I/5 ) calculate no of cells reversed​

Answer 1

Step-by-step explanation:

x = 8,12

depending on the situation

which no of cell has same emf

if x cells have high emf than the remainig 20-x

the net emf= xE-(20-x)E

in this case answer is x=12

if x cell have less emf than remaining ( 20-x) then

net emf= (20-x)E-xE, here answer is x=8

Answer 2

Step-by-step explanation:

I = 20E / R

R = load resistance

I/5 = nE /R

20E / 5R = n E /R

n = 4

no. of cell changing polarity is

20 -4 = 16 /2 = 8 cells changing the polarity.