Question

The threshold wavelength for a metal having work function

Answer 1

Answer:

here is your answer

hope it will helpful

Answer 2

Use the formula W(work function) = HC/∆

Now work function=2.8 eV (given data) =4.48 × 10^-19 joules ( as 1eV = 1.6 × 10–19) …(1)

H=6.626 × 10^34 joules

C = 3.38 ×10^18m/s

Now the equation is

4.48× 10^19 = (6.626×10^–34 × 3.38×10^18 ) / ∆

Which on solving we get

2×10^34 joules = 2×10^24 joules (in angstroms)

This is your final answer.