Browse by Stream
QnA
Home
QnA
Go To Your Study Dashboard

Get Answers to all your Questions

header-bg qa
  • Home
  • Engineering
  • I need help with - Dual Nature of Matter and Radiation - JEE Main

Question contain Statement-1 and Statement-2. Of the four choices given after the statements, choose the one that best describes the two statements.

Statement-1 : When ultraviolet light is incident on a photocell, its stopping potential is V_{0} and the maximum kinetic energy of the photoelectrons is K_{max}. When the ultraviolet light is replaced by X-rays, both V_{0} and K_{max} increase.

Statement-2 :  Photoelectrons are emitted with speeds ranging from zero to a maximum value because of the range of frequencies present in the incident light.

 

Option 1)

Statement-1 is true, Statement-2 is false.

 Option 2)

Statement-1 is true, Statement-2 is true; Statement-2 is the correct explanation of Statement-1.
Option 3)

Statement-1 is true, Statement-2 is true; Statement-2 is not the correct explanation of Statement-1.

 Option 4)

Statement-1 is false, Statement-2 is true.

Answers (1)

best_answer

As we learnt in

Conservation of energy -

h\nu = \phi _{0}+\frac{1}{2}mv^{2}_{max}

h\nu = h\nu _{0}+\frac{1}{2}mv^{2}_{max}

 

h\left ( \nu-\nu _{0} \right )=\frac{1}{2}mv^{2}_{max}

where, h - Plank's constant\ \nu - Frequency\ \nu_{0} - threshold\ frequency\ \phi_{0}- work function

- wherein

 

 From Einstein's photoelectric equation

eV_{0}=h{\nu}-{\phi}                                (1)

Also  eV_{0}=K_{max}                            (2)

When we increase energy of photon (i.e. moving from ultraviolet to X-ray)

V0 increases andhence Kmax also increases.

So Statement (1) is correct.

Statement (2) is wrong as speed of electron varies because of its collision inside the metal before its emission. 

Correct answer is 1.


Option 1)

Statement-1 is true, Statement-2 is false.

This is the correct option.

Option 2)

Statement-1 is true, Statement-2 is true; Statement-2 is the correct explanation of Statement-1.

This is an incorrect option.

Option 3)

Statement-1 is true, Statement-2 is true; Statement-2 is not the correct explanation of Statement-1.

This is an incorrect option.

Option 4)

Statement-1 is false, Statement-2 is true.

This is an incorrect option.

Posted by

perimeter

View full answer

JEE Main high-scoring chapters and topics

Study 40% syllabus and score up to 100% marks in JEE

Similar Questions

Trending Articles/News

anam-khan

JEE Mains 2025 session 1 registration deadline on November 22; apply on jeemain.nta.nic.in
anam-khan

BTech Admission 2025 Live: JEE Mains, SRMJEEE, MET registrations underway; MHT CET syllabus updates
anam-khan

Centre issues coaching guidelines, prohibits centres from using false claims like '100% selection'

Latest Question