Arrange the following in the ascending order of wavelength (\( \lambda \)):
(A) Microwaves (\( \lambda_1 \))
(B) Ultraviolet rays (\( \lambda_2 \))
(C) Infrared rays (\( \lambda_3 \))
(D) X-rays (\( \lambda_4 \))
Choose the most appropriate answer from the options given below:
\[ \lambda_4 < \lambda_3 < \lambda_1 < \lambda_2. \]
Final Answer: \( \lambda_4 < \lambda_3 < \lambda_1 < \lambda_2 \).
The output of the circuit is low (zero) for:

(A) \( X = 0, Y = 0 \)
(B) \( X = 0, Y = 1 \)
(C) \( X = 1, Y = 0 \)
(D) \( X = 1, Y = 1 \)
Choose the correct answer from the options given below:
In a Young's double slit experiment, three polarizers are kept as shown in the figure. The transmission axes of \( P_1 \) and \( P_2 \) are orthogonal to each other. The polarizer \( P_3 \) covers both the slits with its transmission axis at \( 45^\circ \) to those of \( P_1 \) and \( P_2 \). An unpolarized light of wavelength \( \lambda \) and intensity \( I_0 \) is incident on \( P_1 \) and \( P_2 \). The intensity at a point after \( P_3 \), where the path difference between the light waves from \( S_1 \) and \( S_2 \) is \( \frac{\lambda}{3} \), is:

A conducting bar moves on two conducting rails as shown in the figure. A constant magnetic field \( B \) exists into the page. The bar starts to move from the vertex at time \( t = 0 \) with a constant velocity. If the induced EMF is \( E \propto t^n \), then the value of \( n \) is _____. 