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# Three wires of the same material are connected in parallel to a source of emf. Their lengths are in the ratio 1 : 2 : 3 and cross-sectional areas are in the ratio 2 : 4 : 1. Then, the ratio of power dissipated across them will be

$\begin {array} {1 1} (A)\; 6 : 6 : 1 & \quad (B)\;2 : 8 : 3 \\ (C)\;4 : 32 : 3 & \quad (D)\;2 : 8 : 9 \end {array}$

Resistance = $\rho$ l/A
ratio of the resistances are 1/2:2/4:3/1
=> 1:1:6
Power dissipated is in inverse relation to the resistance
Ans : (A)

edited Sep 10, 2014