Why there is no way to separate the internal resistance from the e.m.f. of a cell?

Is internal resistance a defect of a cell? Explain.

Name the device used for measuring the e.m.f. of a cell.

The internal resistance of the cell can be determine by,

On what factors does the internal resistance of a cell depend?

The formula for internal resistance of a cell

A potentiometer wire of length 4 m and resistance 8 Omega is connected in, series with a battery of e.m.f. 2 V and negligible internal resistance. If the e.m.f. of cell balances against length of 217 cm of the wire, find the e.m.f. of cell. When the cell is shunted by assistance of 15 Omega ,the balancing length is reduced to 200 cm. Find the internal resistance of the cell

In a potentiometer experiment, e.m.f. of a cell is balanced by a length of 150 cm on the potentiometer wire. When the cell is shunted by a 10 Omega resistance, the balancing length reduces to 90 cm. What is the internal resistance of the cell?

A current of 3 A flows through certain resistance when a cell is connected across it.The potential difference across the resistance was found to be 4.8 volt. The e.m.f.of cell is 5 volt.Calculate the internal resistance of the cell.

A Daniel cell is balanced on 125 cm length of a potentiometer wire. Now the cells is short-circuited by a resistance 2 ohm and the balance is obtained at 100 cm . The internal resistance of the Dainel cell is