Question

A capacitor of capacitance C is charged with the help of a 200V battery. Its then discharged through a small coil of resistance wire embedded in a thermally insulated block of specific heat capacity 2.5 x 10 2 J/kg and mass 0.1 kg. If the temperature of the block rises by 0.4K, the value of C is a) 500 F b) 500 x 10 -6 F c) 50 F d) 50 x 10 -6 F

Answer 1

the answer of ur question is
 500 x 10 -6
for solution
see the photo

Answer 2

The heat gained by the block             Q = mCvdt                                                                                                                       = 0.1*250*0.4                                                                                                               = 10 J
Energy stored in a capacitor is ½ Cv^2
                                  10 = ½ c (200)^2  
                                    C= 500 * 10^-6 F