12 Physics Current Electricity - Set No : 47 Question No :7
Question No : 7
An electric cable of copper has just
one wire of radius 9 mm. Its resistance is  . This single copper wire of cable
is replaced by 6 different well insulated copper wires each of radius 3 mm.
The total resistance of the cable will now be equal to |
| a) |  | b) |  |
| c) |  | d) |  |
Answer No : 7
(a)For one
wire cable,Resistance,
 For other
wire of cable,Resistance,
  When six
wires each of resistance  are connected in parallel, their
effective resistance will be |