in an electric circuit a battery of 4V is connected and the ammeter shows 0.6A. will the voltmeter show 4V or greater than or less than 4V, justify your answer.

If the potential difference across battery terminals is 4 V when it is not connected to circuit and

current is not drawn from battery , then its EMF is 4 V.

 

When the battery is connected to electric circuit and the circuit is drawing current 0.6A ,

then there is a voltage dropn across the internal resistance of battery that is given as (0.6 × r )

where r is internal resistance. 

 

Hence voltage across battery when it is connected in circuit is  ( 4 - 0.6 × r ) V , which is less than its EMF 4 V