The threshold frequency of silver is 9.71×1015 Hz. What is the work function of silver?

Planck’s constant is 6.63 × 10−34 J · s. Answer in units of eV.

1 Answer
May 16, 2018

W = 40.2W=40.2 "eV"eV

Explanation:

Threshold frequency is related to the work function by the following equation:

f_(0) = frac(W)(h)f0=Wh; where f_(0)f0 is the threshold frequency, WW is the work function, and hh is the Planck constant.

We can rearrange this equation to solve for WW:

Rightarrow W = f_(0) hW=f0h

Let's plug in the given values:

Rightarrow W = (9.71 times 10^(15) times 6.63 times 10^(- 34))W=(9.71×1015×6.63×1034) "J"J

Rightarrow W = 6.43773 times 10^(- 18)W=6.43773×1018 "J"J

However, we need to answer in units of "eV"eV:

Rightarrow W = (frac(6.43773 times 10^(- 18))(1.6 times 10^(- 19)))W=(6.43773×10181.6×1019) "eV"eV

therefore W approx 40.2 "eV"