A wire of copper having length I and area of cross-section A is taken and a current i is flown through it. The power dissipated in the wire is P. If we take an aluminium wire having same dimensions and pass the same current through it, the power dissipated will be
A). P
B). < P
C). > P
D). 2P
> P
Aluminum has a resistivity varying from 2.65 to 2.82 × 10−8 Ω m. The resistivity of copper is generally given as: 1.72 x 10-8 Ω.m. So, since resistivity of aluminium is higher than that of copper, so power dissipated will be greater than P. this is because rest of the factors (l, A and i) are constant.
1. Eclipses occur due to which optical phenomena
3. Nuclear reactors used to produce electricity are based on
4. Resistance of human body in dry condition
7. A spherical ball made of steel when dropped in mercury container
8. A rear-view mirror for driving is