## Question

### Solution

Correct option is

1.9 eV, 4125 Å

The energy (hv1) of the light-photon incident on the surface is equal to the work function W of the surface plus the kinetic energy Ek of the emitted photoelectron.

If the retarding potential is V1, then

= 1.9 eV.

Using the light of another wavelength , we shall have

.

= 4125 Å.

Since the magnetic field does not change the speed of the ejected electrons, there will be no change in the stopping potentials.

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Q10

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