To get maximum current through a resistance of 2.5 Ω , one can use m rows of cells, each row having n cells. The internal resistance of each cell is 0.5 Ω . The values of n and m , if the total number of cells is 45 , are

Question

To get maximum current through a resistance of 2.5 Ω , one can use m rows of cells, each row having n cells. The internal resistance of each cell is 0.5 Ω . The values of n and m , if the total number of cells is 45 , are (A) m= 3, n=15 (B) m= 5, n=9 (C) m= 9, n=5 (D) m= 15, n=3

Tardigrade Admin · Accepted Answer

R=2.5Ω , r=0.5Ω no of rows =m, no of columns in each row =n i=(n E/R + n r / m) total cells ⇒ mn=45 for max. current; R=nr/m, mR=nr m=3, n=15

Q. To get maximum current through a resistance of $2.5 Ω$ , one can use $m$ rows of cells, each row having $n$ cells. The internal resistance of each cell is $0.5 Ω$ . The values of $n$ and $m$ , if the total number of cells is $45$ , are

$m = 3, n = 15$

$m = 5, n = 9$

$m = 9, n = 5$

$m = 15, n = 3$

$R = 2.5Ω, r = 0.5Ω$
no of rows $= m,$ no of columns in each row $= n$
$i = \frac{n E}{R + n r / m}$ total cells $\Rightarrow mn = 45$
for max. current; $R = n r / m, m R = n r$
$m = 3, n = 15$

Q. To get maximum current through a resistance of 2.5Ω , one can use m rows of cells, each row having n cells. The internal resistance of each cell is 0.5Ω . The values of n and m , if the total number of cells is 45 , are

m=3,n=15

m=5,n=9

m=9,n=5

m=15,n=3