# The motorcycle battery has an EMF of 6 V and an internal resistance of 0.5 Ohm. A 5.5 Ohm

**The motorcycle battery has an EMF of 6 V and an internal resistance of 0.5 Ohm. A 5.5 Ohm rheostat was connected to it. Find the current in the rheostat and the voltage at the battery terminals.**

EMF = 6 V.

r = 0.5 ohm.

R = 5.5 ohms.

I -?

U -?

According to Ohm’s law for a closed circuit, the current in the circuit I is directly proportional to the electromotive force of the EMF current source and is inversely proportional to the sum of the external resistance R and the internal resistance of the current source r: I = EMF / (R + r).

I = 6 V / (5.5 Ohm + 0.5 Ohm) = 1 A.

The voltage at the terminals of the battery U is expressed by Ohm’s law for the section of the circuit: U = I * R.

U = 1 A * 5.5 Ohm = 5.5 V.

Answer: the voltage at the battery terminals will be U = 5.5 V and the current in the circuit I = 1 A.