In the given circuit diagram , the cell and ammeter, both have negligible resistance The resistances are identical - Physics - Electricity

Question

In the given circuit diagram , the cell and ammeter, both have
negligible resistance The resistances are identical With the switch
'k' open, the ammeter reads 0 6A What will be the ammeter reading
when the switch is closed?

Vaibhav Tiwari · Accepted Answer

Dear Student, Let the value of each resistance be R1 When key K is open the only two resistance are in a circuit So resultant resistance, in this case, is the parallel combination of two resistances 1R1=1R+1R=2RR1=R2Let potential difference of cell=V voltcurrent, I=0 6 AV=IR1V=0 6×R2=0 3 R

2 Now, when key K is closed, all three resistances are parallel in the circuit Therefore,1R2=1R+1R+1R=3RR2=R3using ohm's law,V=IR20 3R=I×R3I=0 9 A

Regards

In the given circuit diagram , the cell and ammeter, both have negligible resistance. The resistances are identical. With the switch 'k' open, the ammeter reads 0.6A. What will be the ammeter reading when the switch is closed?