The luminous flux of a 1 W sodium vapour lamp is more than that of a 10 kW source of ultraviolet radiation. Comment.

Can two sodium vapour lamps act as coherent sources ? Explain in brief.

Statement - The vapour pressure of 0.1 M sugar solution is more than that of 0.1 M potassium chloride solution. Explanation- Lowering of vapour pressure is directly proportional to the number of species present in the solution.

Calculate the number of photons emitted per second by a 10 W sodium vapour lamp. Assume that 60% of the consumed energy is converted into light. Wavelengths of sodium light =590nm.

Find the luminous flux of 10 W source of 600 nm. The relative luminosity at 600 nm is 0.6.

The luminous flux of a monochromatic source of 1 W is 450 lumen W^-1 . Find the relative luminosity at the wavelength emitted.

If the wavelength of light emitted by a sodium vapour lamp is 5893 A then the numebr of photons emitted in 5 hour by a 50 W lamp will be

A circular area of radius 1.0 cm is placed at a distance of 2.0 m from a poit source.Teh source emits light uniformluy in al directions. The line joining the sorce to the dcentre of the area is normal to the area. It ils found that 2.0xx1^-3 lumen of luminous flux is incident on the area. Calculate the total luminous flux emitted by the soure and teh luminous intensity of the source along the axis of the area.

The overall luminous efficient of a 100 W electric lamp is 25 lumen W^-1 . Assume that light is emitted by the lamp only in the forward half, and is uniformly distributed in al diredctionsin this half. Calculate the luminous flux falling on a plane object of area 1cm^2 placed at a distance of 50 cm from the lamp and perpendicular to the line joining the lamp and the object.

Statement-1. Vapour pressure of liquid ammonia is more than that of water. Statement-2. Molar mass of ammonia is less than that of water.

A resistor of 200 Omega and a capacitor of 15.0muF are connected in series to a 220V , 50Hz source. (a) Calculate the current in the circuit . (b) Calcutalte the voltage (rms) across the resistor and the inductor. Is the algebraic sum of these voltages more than the source voltage? If yes, resolve the paradox.