1. A student blows across the open end of a narrow cylinder which is closed at the other end. If the length of the cylinder is $15.0cm$ and the speed of sound is 340 ms^−1, What is the frequency of the wave at the third harmonic?

2. Sound waves in water travel approximately 4.5 times faster than in air. Which of the following diagrams correctly shows the wavefronts of sound as they pass from air to water?

A.				B.
C.				D.

3. For a wave traveling in a medium, the variation of the particles' displacement with distance travelled is shown in the following graphs, which represent the wave at different moments in time of a wave travelling to the right.

Graph I shows the wave at t=0 s, while graph II is at t=1s.

The time difference between the two graphs is less than the wave's period.

Graph I

Graph II

What is the wave speed?

4. A wave travels on a rope as shown, where $P$ is a point on the rope halfway between the equilibrium position and the maximum displacement.

Which is correct about the direction and magnitude of the velocity of point $P$ after half a period compared to the shown position?

5. A speaker produces a sound near a pipe that is closed at one end by a movable piston. The piston is moved in the shown direction until a sound is first heard from the pipe. At this time, the length of the part of the tube near the speaker is $L$.

What is the distance moved by the piston to hear the next resonant sound from the pipe?

6. A monochromatic beam of light is incident on a double slit arrangement where the slit separation is 9.0×10^−5m and the slit-screen distance is 1.0m. The graph below shows the relative intensity of the light reaching the screen with respect to the distance from the central point of the pattern.

What is the wavelength of the light?

7. A thin beam of monochromatic blue light is incident upon a single slit barrier. The emerging light then passes through a double slit arrangement and falls on a screen some distance away.

An interference pattern is observed on the screen. In order to increase the distance between adjacent fringes, which of the following actions would be appropriate?

8. A light source approaches a stationary receiver at an increasing speed. The frequency of the emitted light is constant. Which graph shows how the observed frequency $f$ by receiver varies with the speed v of the light source?

A.			B.
C.			D.

9. A $50cm$ string that is fixed at both ends produces a standing wave in the third harmonic. The speed of the wave on the string is 200 m s^−1

What is the frequency of oscillation?

10. For a body executing simple harmonic motion, which statement is not possible?

11. A radio with a bright light is placed outside the doorway of long, dark room as shown. A student in a corner near the door can hear the sound of the radio while standing in the dark region of the room.

Which property of waves correctly explains why light does not reach her while the sound does?

12. A radio wave of frequency $90MHz$ travels a distance $d$. The number of wavelengths that can fit into this distance is 6000. What is $d$?

13.  

14. An object executes simple harmonic motion with an amplitude of x0​. Which graph shows the relationship between the kinetic energy Ek​ and the displacement $x$ from the equilibrium position of the object?

A.			B.
C.			D.

15. A string fixed at both ends oscillates in a standing wave as shown with a wavelength of $400mm$.

What is the length of the string?

16. A particle performs simple harmonic motion with a frequency of $0.05Hz$. The distance traveled by the particle in one complete oscillation is $16cm$. Which of the following graphs shows a correct variation of its position?

A.			B.
C.			D.

17. Two identical objects $P$ and $Q$ are connected to identical springs. Both P and $Q$ are performing simple harmonic motion (SHM) around equilibrium level $O$.

The diagram shows positions of $P$ and $Q$ at time $t=0$. Which graph shows how kinetic energy of $P$ and Q vary with time t?

A.				B.
C.				D.

18. A traveling wave is generated on a string tied to a speaker as shown.

Which of the following statements are correct about the travelling wave?

• I.	If the frequency of the sound decreases, the wavelength of the travelling wave increases.
  II.	If the speaker emits a louder sound the amplitude of the travelling wave increases.
  III.	If the frequency of the sound increases, the travelling wave moves along the string faster.

19. Incident light of wavelength $600nm$ is emitted towards two slits separated by $1\mu m$. The interference pattern is observed on a wall. The distance between two adjacent maxima is $1.2m$. What is the distance of the wall from the slits?

20. The diagram shows a beam of light passing from medium $X$ to medium $Y$.

If the angle of incidence of the light increases, which of the following changes can be implemented to keep the angle of refraction the same?

21. A simple pendulum executing simple harmonic motion is released from one end and reaches equilibrium position in $2s$. Just after the equilibrium position, the length of the pendulum is reduced to one-fourth of its initial value because of wrapping around a nail.

What is the period of the simple pendulum?

22. A simple pendulum undergoes simple harmonic motion. The graph shows the variation of a quantity $y$ with horizontal displacement $x$ from the equilibrium position.

Which of the following quantities could be represented by quantity $y$?

23. A traveling source produces sound waves nearby a child. The wavefronts of the sound waves and the position of a child are seen in the figure below.

The frequency of the generated sound waves is $f$. Which of the following is correct for both the direction of motion of the source and the observed frequency of the sound waves by the child?

24. A light and a heavy spring are attached at point $Y$. A pulse was generated in the light spring and incident on the heavy spring. The positions of transmitted and reflected pulses after some time are as shown.

Which of the following is true about the incident pulse?

25. The graph below shows the variation with displacement $x$ of the acceleration $a$ from the equilibrium position of a particle that undergoes simple harmonic motion.

The magnitude of the slope of the graph is directly proportional to