The threshold wavelength for photoelectric emission for a material is `5200 A^(@)`. Will the photoelectrons be emitted when this material is illuminated with monochromatic radiation from 1 watt ultra violet lamp?

Options

A. 50 watt infrared lamp
B. 1 watt infrared lamp
C. 50 watt ultraviolent lamp
D. 10 watt infrared lamp

Answer

To determine whether photoelectrons will be emitted from a material when illuminated with monochromatic radiation from a 1-watt ultraviolet lamp, we need to analyze the given information step by step.

### Step 1: Understand the threshold wavelength
The threshold wavelength for photoelectric emission is given as \( 5200 \, \text{Å} \) (angstroms). This means that for photoelectrons to be emitted, the wavelength of the incident light must be less than this threshold wavelength.

### Step 2: Identify the wavelength of ultraviolet (UV) light
Ultraviolet light has a wavelength range typically between \( 100 \, \text{Å} \) to \( 4000 \, \text{Å} \). This range is important because it helps us determine if the UV light can cause photoelectric emission.

### Step 3: Compare the threshold wavelength with the UV wavelength range
Since the threshold wavelength is \( 5200 \, \text{Å} \) and the UV light has wavelengths that are less than \( 4000 \, \text{Å} \), we can conclude that the UV light has wavelengths that are indeed less than the threshold wavelength.

### Step 4: Conclusion on photoelectron emission
Because the wavelength of the UV light is less than the threshold wavelength of the material, photoelectrons will be emitted when the material is illuminated with the monochromatic radiation from the 1-watt ultraviolet lamp.

### Final Answer
Yes, photoelectrons will be emitted when this material is illuminated with monochromatic radiation from a 1-watt ultraviolet lamp.

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