Question

The work function of cesium metal is 2eV. It means that

• A. The energy necessary to emit electrons from metal surface is 2eV
• B. The energy of electrons emitted from metallic surface is 2eV
• C. The value of photoelectric current is 2eV
• D. The value of threshold frequency is 2eV

Answer 1

The correct option is A The energy necessary to emit electrons from metal surface is 2eV

By definition the work function is the minimum energy (in electron volts) needed to remove an electron from a solid to a point immediately outside the solid surface (or energy needed to move an electron from the Fermi level into vacuum).
Hence, if the work function of cesium metal is 2ev, it means that the energy necessary to emit electrons from metal surface is 2eV.

So, the answer is option (A).