A metal rod of length 10 cm and a rectangular cross-section of 1 cm x 1/2 cm is connected to a battery across opposite faces. Which of the following is true about its resistance? |
maximum when the battery is connected across 10 cm x 1/2 cm faces maximum when the battery is connected across 1 cm x 1/2 cm faces. maximum when the battery is connected across 10 cm x 1 cm faces. same irrespective of the three faces. |
maximum when the battery is connected across 1 cm x 1/2 cm faces. |
The maximum resistance will be achieved when the value of 1/A , is maximum, so that ‘A’ must be minimum and it is minimum when area of cross section is 1 cm x 1/2cm |