AP EAMCET2011PhysicsCapacitance
A fully charged capacitor has a capacitance C . It is discharged through a small coil of resistance wire, embedded in a block of specific heat s and mass m under thermally isolated conditions. If the temperature of the block is raised by T , the potential difference V across the capacitor initially is
Options
- A( 2 m s T C )^2
- B( 2 m s T C )^ 1 / 2
- C( 2 m s T C )
- D2 m s T C
Correct answer
B. ( 2 m s T C )^ 1 / 2
Step-by-step solution
Let V be the potential across the capacitor when it is fully charged, then, energy stored in the capacitor will be = 1 2 C V^2 (where C= capacitance of capacitor) When the capacitor is fully discharged, loss of energy is in the form of heat = H As the system is thermally isolated so, H= 1 2 C V^2 Here, H=m s T 1 2 C V^2=m s T or V= ( 2 m s T C )^ 1 / 2