MCQ
There is a destructive interference between the two waves of wavelength $\lambda$ coming from two different paths at a point. To get maximum sound or constructive interference at that point, the path of one wave is to be increased by
  • A
    $\frac{\lambda }{4}$
  • $\frac{\lambda }{2}$
  • C
    $\frac{{3\lambda }}{4}$
  • D
    $\lambda $

Answer

Correct option: B.
$\frac{\lambda }{2}$
b
(b)With path difference $\frac{\lambda }{2}$, waves are out of phase at the point of observation.

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Similar questions

Relation between emissivity $e$ and absorptive power $a$ is (for black body)
The angular velocity of seconds hand of a watch will be 
During an adiabatic process, the pressure of a gas is found to be proportional to the cube of its absolute temperature. The ratio of $\frac{C_p}{C_v}$ for the gas is:
A p-type semiconductor is:
  1. Positively charged.
  2. Negatively charged.
  3. Uncharged.
  4. Uncharged at 0K but charged at higher ternperatures.
In a Resonance -Coulmn lab experiment to measure the velocity of sound, the first  resonance is obtained at a length $l_1$ and the second resonance at a length $l_2$. Then-
A bullet of mass $0.1\,kg$ is fired with a speed of $100\, m/sec$, the mass of gun is $50\, kg$. The velocity of recoil is ........ $m/sec$
A capacitor with no dielectric is connected to a battery at t = 0. Consider a point A in the connecting wires and a point B in between the plates.
  1. There is no current through A.
  2. There is no current through B.
  3. There is a current through A as long as the charging is not complete.
  4. There is a current through B as long as the charging is not complete.
The specific heat of alcohol is about half that of water. Suppose you have identical masses of alcohol and water. The alcohol is initially at temperature $T_A$ . The water is initially at a different temperature $T_W$ . Now the two fluids are mixed in the same container and allowed to come into thermal equilibrium, with no loss of heat to the surroundings. The final temperature of the mixture will be 
A coin placed on a rotating table just slips when it is placed at a distance of $1\,cm$ from the center. If the angular velocity of the table in halved, it will just slip when placed at a distance of from the centre $............\,cm$
A boat having a length of $3\,metre$ and breadth $2\,metre$ is floating on a lake. The boat sinks by one cm when a man gets on it. Mass of the man is ....... $kg$