Q.

A potential V0 is applied across a uniform wire of resistance R. The power dissipation is P1. The wire is then cut into two equal halves and a potential of V0 is applied across the length of each half. The total power dissipation across two wires is P2. The ratio P2:P1 is x:1. The value of x is _______.               [2023]


Ans.

(16)

P=VI=I2R=V2R

Now R=ρA

If the wire is cut into two equal half, R=R2

Initial P1=V02R

After P2=V02R'×2V02R×4

P2P1=4=x1x=16