Waves

10 JEE Main questions · Physics

Superposition

PhysicsJEE Main 22 Jan 2026, Shift 1·Q21·Numerical·Moderate
Open
Two loudspeakers ( $L_1$ and $L_2$ ) are placed with a separation of 10 m, as shown in figure. Both speakers are fed with an audio input signal of same frequency with constant volume. A voice recorder, initially at point $A$ , at equidistance to both loud speakers, is moved by 25 m along the line $AB$ while monitoring the audio signal. The measured signal was found to undergo 10 cycles of minima and maxima during the movement. The frequency of the input signal is Hz (Speed of sound in air is 324 m/s and $\sqrt5 = 2.23$ )
PhysicsJEE Main 22 Jan 2026, Shift 2·Q8·MCQ·Easy–moderate
Open
In an open organ pipe $\nu_3$ and $\nu_6$ are $3^{\text{rd}}$ and $6^{\text{th}}$ harmonic frequencies, respectively. If $\nu_6 - \nu_3 = 2200$ Hz then length of the pipe is mm. (Take velocity of sound in air is 330 m/s.)
1. (1)275
2. (2)225
3. (3)200
4. (4)250
PhysicsJEE Main 24 Jan 2026, Shift 2·Q9·MCQ·Easy–moderate
Open
The fifth harmonic of a closed organ pipe is found to be in unison with the first harmonic of an open pipe. The ratio of lengths of closed pipe to that of the open pipe is $5/x$ . The value of $x$ is .
1. (1)4
2. (2)2
3. (3)1
4. (4)3
PhysicsJEE Main 24 Jan 2026, Shift 2·Q16·MCQ·Easy–moderate
Open
A point source is kept at the center of a spherically enclosed detector. If the volume of the detector increased by 8 times, the intensity will
1. (1)increase by 8 times
2. (2)increase by 64 times
3. (3)decrease by 8 times
4. (4)decrease by 4 times
PhysicsJEE Main 28 Jan 2026, Shift 2·Q21·Numerical·Easy–moderate
Open
Two tuning forks A and B are sounded together giving rise to 8 beats in 2 s. When fork A is loaded with wax, the beat frequency is reduced to 4 beats in 2 s. If the original frequency of tuning fork B is 380 Hz, then the original frequency of tuning fork A is Hz.

Wave motion

PhysicsJEE Main 21 Jan 2026, Shift 1·Q18·MCQ·Easy–moderate
Open
Two strings (A, B) having linear densities $\mu_A = 2\times10^{-4}$ kg/m and $\mu_B = 4\times10^{-4}$ kg/m and lengths $L_A = 2.5$ m and $L_B = 1.5$ m respectively are joined. Free ends of A and B are tied to two rigid supports C and D, respectively creating a tension of 500 N in the wire. Two identical pulses, sent from C and D ends, take time $t_1$ and $t_2$ , respectively, to reach the joint. The ratio $t_1/t_2$ is:
1. (1)1.08
2. (2)1.90
3. (3)1.67
4. (4)1.18
PhysicsJEE Main 23 Jan 2026, Shift 2·Q25·Numerical·Easy–moderate
Open
The velocity of sound in air is doubled when the temperature is raised from $0^\circ$ C to $\alpha^\circ$ C. The value of $\alpha$ is .
PhysicsJEE Main 28 Jan 2026, Shift 2·Q9·MCQ·Easy–moderate
Open
The speed of a longitudinal wave in a metallic bar is 400 m/s. If the density and Young's modulus of the bar material are increased by 0.5% and 1% respectively then the speed of the wave is changed approximately to m/s.
1. (1)399
2. (2)398
3. (3)402
4. (4)401
PhysicsJEE Main 2 Apr 2026, Shift 1·Q10·MCQ·Easy–moderate
Open
The equation of a plane progressive wave is given by $y = 5\cos\pi\left(200t - \dfrac{x}{150}\right)$ where $x$ and $y$ are in cm and $t$ is in second. The velocity of the wave is m/s
1. (1)120
2. (2)150
3. (3)200
4. (4)300
PhysicsJEE Main 5 Apr 2026, Shift 1·Q23·Numerical·Easy–moderate
Open
A transverse wave on a string is described by $y = 3\sin(36t + 0.018x + \pi/4)$ . Where $x$ , $y$ are in cm and $t$ in seconds. The least distance between the two successive crests in the wave is cm. (Nearest integer) ( $\pi = 3.14$ )