MCQ
Photoelectric emission occurs only when the incident light has more than a certain minimum
- APower
- BWavelength
- CIntensity
- ✓Frequency
✓
Answer
Correct option: D.
Frequency
d
According to Einstein's photoelectric equation
According to Einstein's photoelectric equation
$K_{\max }=h v-h v_0$
Since $K_{\max }$ is positive, the photoelectric emission occurs only if
$h v>h v_0$
$v>v_0$
The photoelectric emission occurs only when the incident light has more than a certain minimum frequency. This minimum frequency is called threshold frequency.
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