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 'Rolling without slipping on a curved surface'

Kindly see the attached pdf. My attempt to solve it, is in it. I'm wondering if my solution is right. My idea is this: At any point of time, the ball may be assumed to be at an incline which is at an angle of θ(kindly see both the pics in the pdf file). The value of θ will continuously change and so will the value of friction. I'm not able to figure out, why my solution is wrong, if it is wrong .
View full post »

Thread 'Struggling to understand the concept of this question (ice cube in water optics question)'

TL;DR Summary: I came across this question from a Sri Lankan A-level textbook. Question - An ice cube with a length of 10 cm is immersed in water at 0 °C. An observer observes the ice cube from the water, and it seems to be 7.75 cm long. If the refractive index of water is 4/3, find the height of the ice cube immersed in the water. I could not understand how the apparent height of the ice cube in the water depends on the height of the ice cube immersed in the water. Does anyone have an...
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