JEE Physics - MCQ Practice Questions

In an n-channel MOSFET operating in saturation region, the drain current is approximately:

The transconductance g_m of a MOSFET in saturation is:

Which semiconductor material has the highest electron mobility at room temperature?

In a light-emitting diode (LED), the color of emitted light depends primarily on:

A solar cell operates as a p-n junction under illumination. The maximum power output occurs at:

In a p-n junction diode, the depletion width is primarily determined by which of the following factors?

A photodiode is reverse-biased to operate in photoconductive mode. What is the primary advantage of this configuration over photovoltaic mode?

A sound wave with frequency 500 Hz travels through air (speed = 330 m/s) and then enters water (speed = 1500 m/s). What happens to the wavelength?

A stationary observer hears a sound from an approaching source. The observed frequency is:

When two coherent light sources interfere, the condition for destructive interference is:

A wave equation is given as y = 5sin(2πx/4 - 2πt/2). The amplitude and frequency are:

The intensity of a sound wave is I. If the amplitude is doubled and frequency is halved, the new intensity will be:

A pipe closed at one end and open at the other has a length of 0.5 m. The fundamental frequency is (speed of sound = 340 m/s):

Two sources of sound have intensities I₁ and I₂. The ratio of their amplitudes is:

When a wave reflects from a denser medium, the phase change is:

In Young's double slit experiment, if the distance between slits is d, distance to screen is D, and wavelength is λ, the fringe width is:

For a stationary wave on a string fixed at both ends of length L = 1 m, the fundamental frequency is 100 Hz. What is the velocity of the transverse wave on the string?

A source of frequency 500 Hz moves towards a stationary observer at 10 m/s. The speed of sound is 330 m/s. What is the apparent frequency heard by the observer?

A string of length 2 m vibrates in its third harmonic. The number of nodes (excluding ends) is:

A pipe open at both ends resonates at a frequency of 500 Hz for the fundamental mode. If it is closed at one end, the fundamental frequency becomes: