The internal resistance of primary cell is `4Omega` it generater a current of `0.2A` in which chemical resistance connected is providing the current is

Options

A. `0.42J//s`
B. `0.24J//s`
C. `5J//s`
D. `1J//s`

Answer

D

Explanation

Here `r = 4Omega,I = 0.2A,R= 21Omega`
if `epsilon` is emf of the cell , then
`epsilon= I(R+r) = 0.2(21+4) = 5` volt
Rate at which of the energy is consumed
`= epsilon I = 5 xx 0.2= IJ//s`