When an incident light is targeted to a metallic surface, photoelectrons are ejected as a result.The number of photoelectrons ejected are
Correct answer: D. Directly proportional to the intensity of the incident light.
- A. Inversely proportional to the frequency of the incident light.
- B. Directly proportional to the frequency of the incident light.
- C. Inversely proportional to the intensity of the incident light.
- D. Directly proportional to the intensity of the incident light.
Explanation
In the photoelectric effect, the number of photoelectrons ejected from a metallic surface is directly proportional to the intensity of the incident light. This is because the intensity of light refers to the number of photons hitting the surface per unit time. More photons mean more chances for photoelectrons to be ejected.Option A is incorrect because the frequency of light affects the energy of the ejected photoelectrons, not their number. Option B is incorrect for the same reason. Option C is incorrect because increasing light intensity increases, not decreases, the number of ejected photoelectrons.
Last updated
About Photons and the Particle Model of Light
The particle model treats light as photons with energy E equals hf and momentum related to wavelength. Questions involve the photoelectric effect, work function, threshold frequency, stopping potential and photon energy, while distinguishing particle behaviour from the wave description of interference and diffraction.
Practise Dawn of Modern Physics
739 free Dawn of Modern Physics MCQs from Physics, each with the correct answer and an explanation. Unlimited attempts, no account needed.
Exams that ask Physics questions like this
Physics is on 13 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.
Related questions
A ball of mass 1g is moving with a velocity of 10³ m/s. The De_Broglie wavelength of the ball is:
A beam of light of wavelength "λ" and with illumination "L" falls on a clean surface of sodium. If "N" photoelectron are emitted each with kinetic energy E:
A change in energy of a photon occurs when it collides with an electron at rest and is known as:
A device whose working is based upon photoelectric effect is:
A particle of mass 5 mg moves with a speed of 8 m/s. Calculate its de Broglie wavelength (h = 6.63 x 10^-34 J s).