Q.

Figure shows three resistor configurations R1, R2 and R3 connected to a 3 V battery. If the power dissipated by the configuration R1, R2 and R3 is P1, P2 and P3, respectively, then                      [2008]

1 P1>P2>P3  
2 P1>P3>P2  
3 P2>P1>P3  
4 P3>P2>P1  

Ans.

(3)

We know power, P=V2R

And V is constant in all three cases.    P1R

Case (i)

This is a case of balanced Wheatstone bridge R1=1Ω

Case (ii)

1R2=12+11+12R2=24=12 52

Case (iii)

Thus R3=2Ω

Since, R2<R1<R3    P2>P1>P3