Question

\[ \int_{-\pi/2}^{\pi/2} |\sin x| dx \text{ equals to} \]

• A. 0
• B. 1
• C. -1
• D. 2

Hint:

The Lande interval rule determines energy level separations in multiplets.

Answer 1

The Correct Option is D

\(|\sin x|\) is an even function, symmetric about y-axis. \[ \int_{-\pi/2}^{\pi/2} |\sin x| dx = 2 \int_0^{\pi/2} \sin x dx = 2 [-\cos x]_0^{\pi/2} = 2 (0 + 1) = 2 \]