What is the threshold wavelength for this surface?

[kavamo]

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

 

[rock.freak667]

Can you please show how you got those answers?

 

[kavamo]

Thanks for your quick response. I figured out what I was doing wrong and solved it.