The potential difference between the terminals of a 6.0V battery is 7.2 V when it is being the terminals of a 6.0V battery is 7.2V when it is being charged by a current of 2.0A.When is the internal resistance of the battery?

Explanation

`v = E + ir
` rArr 7.2 = 6 + 2 xx r `
` rArr = 1.2 = 2r rArr r = 0.6 Omega ` .