this is the same objective question from 2 different well followed books one HCV and the DC Panday

DC Panday (Optics and modern physics) Page no. 210 Q. 39

HCV part 2 pg no. 394.

Q. The potential difference applied to an X-Ray tube is increased.As a result in the emitted radiation, (Multi answered)

a) the intensity increases

b) the miimum wavelength increases

c) the intensity remains unchanged

d) the minimum wavelength decreases

the answer given in HCV is (C) and (D)

while DCPanday says it (A) and (D)

please tell which is the correct answer. and do give an apt explanation coz i am terribly confused and am wasting a lot of time on this thing..

When dealing with X-ray tubes and the effects of increasing the potential difference (voltage) applied to them, it's essential to understand how this change impacts both the intensity and the wavelength of the emitted radiation. Let's break down the question and the options provided to clarify the confusion.

Understanding X-Ray Production

X-rays are produced when high-energy electrons collide with a metal target in the X-ray tube. The energy of these electrons is determined by the potential difference applied across the tube. When you increase this potential difference, several things happen:

• Increased Energy of Electrons: The electrons gain more kinetic energy as they are accelerated by the higher voltage.
• Higher Energy X-rays: When these high-energy electrons strike the target, they can produce X-rays with higher energy.

Effects of Increasing Potential Difference

Now, let's analyze the options based on these principles:

• Option A: The intensity increases - This is correct. As the potential difference increases, more electrons gain sufficient energy to produce X-rays, leading to an increase in the overall intensity of the emitted radiation.
• Option B: The minimum wavelength increases - This is incorrect. The minimum wavelength of the emitted X-rays is inversely related to the energy of the photons produced. As the energy increases (due to higher voltage), the minimum wavelength actually decreases.
• Option C: The intensity remains unchanged - This is incorrect. As explained, increasing the potential difference increases the intensity of the emitted X-rays.
• Option D: The minimum wavelength decreases - This is correct. Higher energy electrons produce X-rays with shorter wavelengths, so as the voltage increases, the minimum wavelength decreases.

Conclusion on the Correct Answers

Based on the analysis, the correct answers are:

• A: The intensity increases
• D: The minimum wavelength decreases

Therefore, the answer provided by DC Panday is accurate, while HCV's assertion that the intensity remains unchanged is not correct. It’s crucial to remember that in X-ray production, increasing the potential difference not only enhances the intensity but also reduces the minimum wavelength of the emitted radiation. This understanding should help clarify your confusion and guide you in similar questions in the future.