Nuclei — Physics STD 12 Science — Question

What is the average binding energy per nucleon over a wide range?

When the intensity of magnetic field is increased four times the time period of suspended magnetic needle becomes :

In the adjoining figure, four capacitors are shown with their respective capacities and the P.D. applied. The charge and the P.D. across the 4μF  capacitor will be

(a) 600 μC; 150 volts

(b) 300 μC; 75 volts

(c) 800 μC; 200 volts

(d) 580 μC; 145 volts

P-N junction diode is used as :

Two condensers of capacities 2C and C are joined in parallel and charged upto potential V. The battery is removed and the condenser of capacity C is filled completely with a medium of dielectric constant K. The p.d. across the capacitors will now be

(a)

(b)

(c)

(d)

The energy of a hydrogen atom in its ground state is -13.6eV. The energy of the level corresponding to the quantum number n = 2 (first excited state) in the hydrogen atom is

(a) – 2.72 eV

(b) – 0.85 eV

(c) – 0.54 eV

(d) – 3.4 eV

When hydrogen atom is in its first excited level, its radius is .... its ground state radius

(a) Half

(b) Same

(c) Twice

(d) Four times

Two bulbs each marked 100 W, 220 V are connected in series across 220 V supply. The power consumed by them, when lit, is