# The Naked Scientists Forum

### Author Topic: Calculate the threshold wavelength of the metal.  (Read 5098 times)

#### Chikis

• Jr. Member
• Posts: 35
##### Calculate the threshold wavelength of the metal.
« on: 21/07/2014 01:46:13 »
Caesium metal of work function is illuminated with radiations of wavelength . Calculate the:
(i)threshold wavelength of the metal;
(ii)maxium energy of liberated elecrons.

Since threshold frequency and threshold wavelenght are not the same, am confused of the formula to use.
What is the best formula to use? Should I use or should use

#### evan_au

• Neilep Level Member
• Posts: 3955
• Thanked: 228 times
##### Re: Calculate the threshold wavelength of the metal.
« Reply #1 on: 21/07/2014 10:20:49 »
Would it make more sense if you used the definition that Frequency f = c/λ = (Speed of light)/wavelength.

Perhaps those equations are equivalent?

#### The Naked Scientists Forum

##### Re: Calculate the threshold wavelength of the metal.
« Reply #1 on: 21/07/2014 10:20:49 »