1. A laser beam passes through a narrow slit and incident on a screen. A diffraction pattern is observed on the screen. The variation of intensity $I$ of light on the screen with distance $x$ is seen in the graph below.

Which of the following graphs best represents intensity distribution with distance when the slit is replaced by one of greater width? The original distribution is shown with a dashed line.

A.				B.
C.				D.

2. A student carried out an experiment using a laser beam incident on double slits with negligible widths. An interference pattern is observed on a distant screen.

Which of the following is correct for the pattern observed on the screen when the slits of non-negligible widths are used with the same slit separation?

I. It is modulated with the single slit diffraction effect
II. Central maximum is brighter
III. Fringe spacing is larger

3. In Young’s double-slit experiment, monochromatic light is incident on two slits and a diffraction pattern is observed on a distant screen. The graph shows the variation of intensity with distance from the centre of the pattern.

The slits are replaced by two slits with negligible width. What is the effect of this change on the interference pattern?

4. A light ray is incident on a semicircular glass block from the air. The glass has a greater refractive index than air. Which diagram correctly represents a possible path of the light ray as it enters and leaves the block?

A.				B.
C.				D.

5. A taut string on a guitar is fixed at both ends.

6. A beam of parallel light with a wavelength of λ is incident on a narrow slit. A diffraction pattern is formed on a distant screen. The angle of diffraction between the central maximum and the first minimum is θ. What would be the angle of the first diffraction minimum for the light with a wavelength of 3λ?

7. Wavefronts travel across a boundary between two media as shown.

Which of the following correctly describes the change, if any, in the speed, wavelength and frequency of the waves as they pass from across the boundary?

8. A spring-mass system executes simple harmonic motion with an amplitude of $20cm$ and maximum elastic potential energy of $100J$. What is the displacement of the mass when the elastic potential energy of the system is $25J$?

9. 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?

10. For an object undergoing simple harmonic oscillation, the graphs show the variation of two quantities for the object with time $t$.

Which two quantities could be represented by these graphs?

11. 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?

12. A boy tied two identical ropes to a fixed wall for a fitness exercise. He shakes the ropes to form waves.

A point on the right rope oscillates with a period of $0.4s$. A point on the left rope oscillates with a period of $0.2s$.

What is the ratio = wavelength of right rope/wavelength of left ?

13. A monochromatic beam of light is incident on a double slit arrangement where the slit separation is 9.0×10^−5 m 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?

14. A mass $M$ hangs in equilibrium on a spring. The mass is pulled down 10$cm$ below the equilibrium position and released. It oscillates vertically about the equilibrium position performing simple harmonic motion.

If it takes 0.5 $s$ after release to return to its equilibrium position, which of the following is true for its first oscillation?

15. A wave is incident on a boundary between two media, $X$ and $Y$. The wave travels faster in medium $Y$ than in medium $X$

Which of the following diagrams shows a possible path for this wave?

A.				B.
C.				D.

16. 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.

17. 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 ms^−1

What is the frequency of oscillation?

18. A body performs simple harmonic motion (shm). Which of the following could be the speed against the time graph for one period of motion?

A.				B.
C.				D.

19. The graph shows the variation with time $t$ of the displacement $s$ of an object suspended by a spring. At what time is the acceleration in the negative direction at a maximum??

20. In a single slit diffraction experiment, incident light passes through an aperture and a diffraction pattern is observed on a distant screen. $X$ is a point on the screen between the second-order minimum and the first-order minimum. $Y$ is a point at the centre of the principal maximum.

Which one of the following could be the ratio of the intensity of light on X to the intensity of light on $Y$?

21. A mass-spring system has a period of T0. Another mass-spring system has a mass twice as large with a spring that requires four times as much force to obtain the same extension as the first system.

What is the new period in terms of T0?

22. 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?

23. 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?

I. Medium X can be replaced with another medium which has a lower refractive index.
II. Medium X can be replaced with another medium which has a higher refractive index.
III. Medium Y can be replaced with another medium which has a higher refractive index.

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

25. 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.