What is the threshold wavelength for this surface?

AI Thread Summary
The discussion focuses on calculating the maximum kinetic energy of ejected electrons from a surface with a work function of 2.24 eV when exposed to radiation of 419 nm. The relevant equation used is E=hf, where E is energy, h is Planck's constant, and f is frequency. The user initially struggled with the calculations but later figured out the correct approach. The threshold wavelength for the surface is also sought, indicating the minimum wavelength required to eject electrons. Overall, the thread emphasizes the importance of understanding the relationship between work function, wavelength, and kinetic energy in photoelectric effects.
kavamo
Messages
45
Reaction score
0

Homework Statement


A surface of a substance has a work function of 2.24 eV.
(a) What is the maximum kinetic energy of ejected electrons if the incident radiation is of wavelength 419 nm?
eV

(b) What is the threshold wavelength for this surface?
nm

Homework Equations


E=hf


The Attempt at a Solution


7.15x10^14
4.74E^-14
 
Physics news on Phys.org


Can you please show how you got those answers?
 


Thanks for your quick response. I figured out what I was doing wrong and solved it.
 
Thread 'Voltmeter readings for this circuit with switches'

Thread 'Voltmeter readings for this circuit with switches'

TL;DR Summary: I would like to know the voltmeter readings on the two resistors separately in the picture in the following cases , When one of the keys is closed When both of them are opened (Knowing that the battery has negligible internal resistance) My thoughts for the first case , one of them must be 12 volt while the other is 0 The second case we'll I think both voltmeter readings should be 12 volt since they are both parallel to the battery and they involve the key within what the...
View full post »
Thread 'Correct statement about a reservoir with an outlet pipe'

Thread 'Correct statement about a reservoir with an outlet pipe'

The answer to this question is statements (ii) and (iv) are correct. (i) This is FALSE because the speed of water in the tap is greater than speed at the water surface (ii) I don't even understand this statement. What does the "seal" part have to do with water flowing out? Won't the water still flow out through the tap until the tank is empty whether the reservoir is sealed or not? (iii) In my opinion, this statement would be correct. Increasing the gravitational potential energy of the...
View full post »

Similar threads

Threshold Wavelength for Photoelectric Effect - 6.476103179e-19J
Replies
7
Views
8K
Threshold frequency and wavelength of electrons in the photoelectric effect
Replies
4
Views
14K
Wavelength = deBroglie Wavelength?
Replies
11
Views
2K
Calculating energy/work of a quantum
Replies
2
Views
2K
Wavelength-stopping potential dependence
Replies
5
Views
2K
Photoelectric Effect Graph and Work Function Questions
Replies
25
Views
4K
The thickness of glass and the longest wavelength
Replies
1
Views
4K
Calculate the wavelength when electron transits.
Replies
2
Views
1K
Kinetic energy and velocity of electron after compton scatte
Replies
1
Views
4K
Photoelectric effect calculation
Replies
8
Views
3K

Hot Threads

Recent Insights

Back
Top