If voltage across a bulb rated $$220 \mathrm{~V}, 100 \mathrm{~W}$$ drops by $$2.5 \%$$ of its rated value, then the percentage of the rated value by which the power would decrease is
A long solenoid has 500 turns, when a current of $$2 \mathrm{~A}$$ is passed through it, the resulting magnetic flux linked with each turn of the solenoid is $$4 \times 10^{-3} \mathrm{~Wb}$$, then self induction of the solenoid is
A fully charged capacitor $$C$$ with initial charge $$q_0$$ is connected to a coil of self inductance $$L$$ at $$t=0$$. The time at which the energy is stored equally between the electric and the magnetic field is
A magnetic field of flux densiity $$1.0 \mathrm{~Wb} \mathrm{~m}^{-2}$$ acts normal to a 80 turn coil of $$0.01 \mathrm{~m}^2$$ area. If this coil is removed from the field in $$0.2 \mathrm{~s}$$, then the emf induced in it is