A small plate of a metal is placed at a distance of 2m from a monochromatic light source of wavelenght `4.8xx10^(-7)m` and power 1.0 Watt. The light falls normally on the plate. Find the number of photons striking the metal plate per square metre per second.

A small plate of a metal (work function =1.7eV ) is placed at a distance of 2m from a monochromatic light source of wavelength 4.8xx10^(-7)m and power 1.0watt. The light falls normally on the plate. Find the number of protons striking the metal plate per square metre per second. If a constant magnetic field of strength 10^(-4)T is applied parallel to the metal surface, find the radius of the largest circular path followed by the emitted photoelectron. (use h=6.63xx10^(-34)Js , mass of electron= 9.1xx10^(-31)kg , charge of electron= 1.6xx10^(-19)C

A monochromatic radiation of wavelength lamda and intensity I is incident on a plate of area A. Find the number of photons striking the plate per second.

A 200 W bulb emits monochromatic light of wavelenght 1400 A and only 10% of the energy is emitted as light. The number of photons emitted by the bulb per second will be

A monochromatic light source of frequency 6xx10^(14)Hz is emitting energy at the rate 2xx10^(-3)J//s . Calculate the number of photons emitted per seconds by source.

Find the number of photons emitted per second by a 25 watt source of monochromatic light of wavelength 6000Å .