A metallic surface emits electrons when it is irradiated with a yellow light source of power 25 Watts. What happens to the emission of the electrons if one yellow light source is replaced by two violet light sources of same power?

The number of emission of electrons will increase but the maximum velocity remains the same.

The number of emission of electrons will decrease but the maximum velocity remains the same.

Both the number of emission of electrons and the maximum velocity will decrease.

Both the number of emission of electrons and the maximum velocity will increase.

I think A

Both the number of emission of electrons and the maximum velocity will increase

To determine what happens to the emission of electrons when one yellow light source is replaced by two violet light sources of the same power, we need to consider a few key concepts.

1. The photoelectric effect: This phenomenon occurs when light, or photons, strike a material surface and cause the emission of electrons, known as photoelectrons.

2. The Einstein equation: This equation relates the energy of a photon with its frequency (or wavelength). It is given by E = hν, where E represents the energy, h is the Planck's constant, and ν is the frequency of the photon.

3. Power: Power is the rate at which energy is transferred or converted. In this case, it represents the rate at which energy is delivered by the light source to the metallic surface.

Now, let's analyze the situation. The power of the yellow light source is given as 25 Watts. When it irradiates the metallic surface, it emits electrons. If we replace this yellow light source with two violet light sources of the same power, we need to consider the differences between the yellow and violet light.

Yellow light has a longer wavelength and lower frequency compared to violet light. This means that yellow light photons carry less energy compared to violet light photons. Therefore, the violet light sources will deliver more energy per photon to the metallic surface.

When more energy is delivered to the metallic surface, the emitted electrons would possess higher kinetic energy and, therefore, higher maximum velocity. This corresponds to option D: "Both the number of emissions of electrons and the maximum velocity will increase."

Hence, the correct answer is D: Both the number of emissions of electrons and the maximum velocity will increase.