Question

A cell of internal resistance r connected across an external resistance R can supply maximum current when
A) R=r
B)R>r
C)R=r/2
D)R=0​

Answer 1

Answer:For current in the external circuit to be maximum, the total resistance (r+R) should be minimum. r is constant for a cell, so R should be zero. This value of R is not mentioned explicitly in any of the given options.

Therefore, the correct option must be D.

Answer 2

The current will be maximum when R=r.

Explanation:

• The internal resistance r is due to the potential drop in a circuit and when the external resistance is equal to r, then maximum current will flow through the circuit.
• For a series combinations, I= nE/nr+R,
• This means that when cells are in series, if R value is higher, the value of current will be less and at the same time, if r and R are equal, the overall resistance will be decreased which enhances the flow of current resulting in maximum current flow.

To know more:

1) What is internal resistance

https://brainly.in/question/6228196.

2) What is internal resistance of conductor? ​

https://brainly.in/question/14619886