If the frequency of incident light in a photoelectric experiment is doubled, then stopping potential will

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TestHub · Accepted Answer

According to Einstein's photoelectric equation, the stopping potential $V_{1}$ for an incident light of frequency $ν$ is given by

$e V_{1} = h ν - Φ$

where $Φ$ is the work function of the metal.

When the frequency is doubled, the new stopping potential $V_{2}$ is given by

$e V_{2} = h (2 ν) - Φ$

$e V_{2} = 2 h ν - Φ$

Substituting $h ν = e V_{1} + Φ$ into the equation, we get

$e V_{2} = 2 (e V_{1} + Φ) - Φ$

$e V_{2} = 2 e V_{1} + Φ$

$V_{2} = 2 V_{1} + \frac{Φ}{e}$

Since the work function $Φ$ is positive, $V_{2} > 2 V_{1}$ .

Thus, the stopping potential becomes more than double.

Answer: become more than double.

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