When light of wavelength 240 nm falls on a potassium surface, electrons having a maximum kinetic energy of 2.93 ev are emitted. find values for the following.when light of wavelength 240 nm falls on a potassium surface, electrons having a maximum kinetic energy of 2.93 ev are emitted. find values for the following. (a) the work function of potassium
ev
(b) the cutoff wavelength
nm
(c) the frequency corresponding to the cutoff wavelength
hz
Solved
Show answers
More tips
- H Health and Medicine How Did Inna Lose Weight on Dom 2?...
- H Health and Medicine Coughing: Causes, Types, and Treatment Methods...
- H Health and Medicine How to Treat the Flu: A Comprehensive Guide...
- O Other What is a Disk Emulsifier and How Does it Work?...
- F Family and Home What does a newborn need?...
- F Family and Home Choosing the Right Car Seat for Your Child: Tips and Recommendations...
- F Food and Cooking How to Get Reconfirmation of Registration?...
- C Computers and Internet How to Get Rid of Spam in ICQ?...
- A Art and Culture Who Said The Less We Love a Woman, the More She Likes Us ?...
- F Family and Home How to Get Rid of Your Neighbors?...
Answers on questions: Physics
- P Physics A charged cell phone has chemical energy stored in its battery. As you use your phone, the amount of chemical energy in the battery decreases. Why is this not a violation...
- P Physics The output power of a solar panel is the rate of transfer a) current b) electrons c) energy d) voltage...
- P Physics A14.8 kg child sits in a 1.3kg swing...
- P Physics A small wooden block with mass 0.775 kg is suspended from the lower end of a light cord that is 1.62 m long. The block is initially at rest. A bullet with mass 0.0122 kg...
- P Physics Imagine a monkey is sitting inside a barrel turned on its side. A cruel elephant pushes the barrel down a hill and the monkey starts to roll inside the barrel. This particular...
- P Physics a student lifts a toy car from a bench and places the toy car at the top of a slope describe an energy transfer that occurs when the student lifts the toy car from the bench...
- E Engineering There are two piston-cylinder systems that each contain 1 kg of an idea gas at a pressure of 300 kPa and temperature of 350 K. The two systems then undergo two different...
- M Mathematics A bag has 11 brown marbles. Half of the blue marbles are made of plastic. A marble is selected at random from the bag. What is the probability that it is a blue, plastic...
- M Mathematics Gelb Company currently manufactures 54,000 units per year of a key component for its manufacturing process. Variable costs are $5.15 per unit, fixed costs related to making...
- S Spanish What key detail supports the fact that Dr. Milstein made an important contribution to society? He earned very prestigious global recognition. He taught medicine lessons...
Ответ:
A) We want to find the work function of the potassium. Apply this equation:
E = 1243/λ - Φ
E = energy of photoelectron, λ = incoming light wavelength, Φ = potassium work function
Given values:
E = 2.93eV, λ = 240nm
Plug in and solve for Φ:
2.93 = 1243/240 - Φ
Φ = 2.25eV
B) We want to find the threshold wavelength, i.e. find the wavelength such that the energy E of the photoelectrons is 0eV. Plug in E = 0eV and Φ = 2.25eV and solve for the threshold wavelength λ:
E = 1243/λ - Φ
0 = 1243/λ - Φ
0 = 1243/λ - 2.25
λ = 552nm
C) We want to find the frequency associated with the threshold wavelength. Apply this equation:
c = fλ
c = speed of light in a vacuum, f = frequency, λ = wavelength
Given values:
c = 3×10⁸m/s, λ = 5.52×10⁻⁷m
Plug in and solve for f:
3×10⁸ = f(5.52×10⁻⁷)
f = 5.43×10¹⁴Hz
Ответ:
CRYSTAL
MANY ATOMS THAT ARE ARRANGE IN A REGULAR PATTERN
1:1
Explanation: