When a certain photosensitive surface is illuminated with monochromatic light of frequency v, the stopping potential for the current is –V₀/2. When the surface is illuminated by monochromatic light of frequency v/2, the stopping potential is – V₀. The threshold frequency for photoelectric emission is :

A parallel plate capacitor with plates of area 1 m² each, are at a separation of 0.1 m. If the electric field between the plates is 100 N/C, the magnitude of charge on each plate is :

(Take $$\varepsilon $$₀ = 8.85 $$ \times $$ 10^$$-$$12 $${{{C^2}} \over {N - {m^2}}}$$)

A paramagnetic material has 10²⁸ atoms/m³. Its magnetic susceptibility at temperature 350 K is 2.8 $$ \times $$ 10^–4. Its susceptibility at 300 K is :

In the given circuit diagram, the currents, I₁ = – 0.3 A, I₄ = 0.8 A and I₅ = 0.4 A, are flowing as shown. The currents I₂, I₃ and I₆, respectively, are :