• # question_answer A wire when connected to 220V mains supply has power dissipation ${{P}_{1}}$. Now the wire is cut into two equal pieces which are connected in parallel to the same supply. Power dissipation in this case is ${{P}_{2}}$. Then ${{P}_{2}}:{{P}_{1}}$ is              [AIEEE 2002] A)            1     B)            4 C)            2     D)            3

When wire is cut into two equal parts then power dissipated by each part is $2{{P}_{1}}$ So their parallel combination will dissipate power ${{P}_{2}}=2{{P}_{1}}+2{{P}_{1}}=4{{P}_{1}}$            Which gives $\frac{{{P}_{2}}}{{{P}_{1}}}=4$