Photoelectric Effect Intensity and Photoelectrons – Rankers Physics

Photoelectric Effects and deBroglie Equation: Practice Problem & Solution

In the following question, a statement of Assertion (A) is followed by a statement of Reason (R). Assertion (A): On increasing intensity of light, more number of photoelectrons are emitted. Reason (R): The number of electrons emitted does not depend on intensity of incident radiations  
Both (A) & (R) are true and the (R) is the correct explanation of the (A)
Both (A) & (R) are true but the (R) is not the correct explanation of the (A)
(A) is true statement but (R) is false
Both (A) & (R) are false statements

Solution Explained:

To solve this problem, we apply the core principles of Photoelectric Effects and deBroglie Equation. Understanding the underlying formula is key to arriving at the correct answer below:

The number of emitted photoelectrons per second is directly proportional to the intensity of incident light above the threshold frequency. Thus, Assertion is true but Reason is false.

Leave a Reply

Your email address will not be published. Required fields are marked *

Similar Practice Questions

Explore conceptually related problems to test your knowledge.

1. An electron of mass m, when accelerated through a potential difference V, has de-Broglie wavelength $\lambda$. The de-Broglie wavelength associated with a proton of mass M accelerated through the same potential difference, will be (1995)
2. Assertion (A): For the scattering of \(\alpha\)-particles at a large angles only the nucleus of the atom is responsible. Reason (R): Nucleus is very heavy in comparison to electrons.  
3. A 200 W sodium street lamp emits yellow light of wavelength 0.6 μm. Assuming it to be 25% efficient in converting electrical energy to light, the number of photons of yellow light it emits per second is :
4. The wavelength of the first line of Lyman series for hydrogen atom is equal to that of the second line of Balmer series for a hydrogen like ion. The atomic number Z of hydrogen like ion is: (2011 Pre)
5. Assertion (A): Increase in intensity of light increases the kinetic energy of photoelectrons. Reason (R): At stopping potential, no current flows in the circuit.