A monochromatic laser beam is shone into the surface of a tank fila6-21gk3-api kxy3hj1f b f g8rvsw1zled with water. The effects on the laser beam due to the water awgvh-j askz 281xkfar - 1p6yf33i1gbre observed.

How will the properties of the light be affected by the water?

  In a Young's double-slit experiment, the spacing of the double slitssye339fnpd36b jhkbn;1 th vuw7;:v y is $d$ and the distance between the slits and the screen on which fringes are formed is $D$. When monochromatic light of wavelength $\lambda$ is incident on the slits the distance between adjacent fringes on the screen is $s$.

Which row shows another arrangement that produces a fringe spacing of $s$ ?

  A sound source $X_{1}$ is positioned $w \; cm$ to the left of sound source $X_{2}$. Both sound sources are $y \; m$ below the detection line $A B$. $A B$ runs parallel to $X_{1} X_{2}$. When a sound detector is slowly moved along the line $A B$, a maxima is first detected at $P$, followed by a minima at $Q$, with another maxima at $R$ and a minima at $S$. $P Q R S$ are all equidistant apart with $X_{1} S=X_{2} S$.

Which one of the following is a correct expression for the wavelength of the sound?

  A student is investigating thcmbvk5:* 9fju yig* r, 45qfvje interference of waves. They set up coherent waves *v5b v9ryu5, fc*gji q4kf: mjproduced at points $\mathrm{S}$ and $\mathrm{T}$ and travel outwards in all directions.

The line $X Y$ is halfway between $S$ and $T$ and perpendicular to the joining line $S$ and $T$. The distance $X Y$ is much greater than the distanceST.



Which line or lines would an interference pattern be seen along?

  Ray diagrams can be used to show the reflection, re 3li 9qbv0d+8u z8tttlfraction and transmission of light at the boundary betwee89+ tt3ublvl80 qti dzn media.


In the diagram, what feature does $X$ represent?

  $\mathrm{K}$ is the source of a wave of frequency $25 \mathrm{~Hz}$.



The wave travels to point $M$ by two routes, $K \rightarrow L \rightarrow M$ and $K \rightarrow M$. The speed of the wave is $15 \mathrm{~m} \mathrm{~s}^{-1}$.

What is the path difference between the two waves at M in terms of the wavelength $\lambda$ of the waves?

  When does diffraction occuckt7eh 8vn. -zgf2vwh)+hu5 pr?

  The diagram below shows an arrangemees) 7 kgz /c1w8fhev0ont used to investigate double slit interference us7e1hckfew8)g/ v0s oz ing microwaves.



The diagram below shows the view from above:



The microwaves from the transmitter are polarised. These waves are detected by the aerial in the microwave detector (probe). The aerial is a vertical metal rod.

The detector is moved along the dotted line UY. As it is moved, maximum and minimum signals are detected. Maximum signals are first detected at points $\mathrm{V}$ and $W$. The next maximum signal is detected at the position $X$.

The distances between each of the two slits, $S_{1}$ and $S_{2}$ and the microwave receiver when the aerial is in position $\mathrm{X}$ are $\mathrm{S}_{1} \mathrm{X}=$ $0.3335 \mathrm{~m}$ and $\mathrm{S}_{2} \mathrm{X}=0.3615 \mathrm{~m}$

Find the wavelength of the microwave and select the two correct reasons that explain why the signal strength falls to a minimum between $U$ and $V$, and between $V$ and W.

  Which of the following images shown below best represejrf )ib1 h5.27s* (bsbjdsymdnts the path of visible light traveling throughfdisb1ss (ybj md *)5jh7 br2. a glass prism?

  Which phrase correctly completes the following se0n p-4+ho 3tyi +rwqoentence?

In a ray diagram showing reflection, the angle of incidence is the angle between

  A double slit interference experiment -a -,gt1qh uzcis conducted using monochromatic light of wavelength ,z1h-a-c qgtu$\lambda$. The centre of the observed pattern is a bright fringe.



What is the path difference between two waves which interfere to give the second dark fringe from the centre?

  Which row correctly describes the 0.s 5n9 fkdexicr- (gvconditions for constructive and destructive interferec 9f0vne. -s(r kd5xgince in a double-slit diffraction pattern?

  Which property of a wave does not change g58ehs s77pgsnm mb8-as a result of refraction?

  Which image shows the correct rayk.z(3yhpq/d;b h hf)t diagram for light passing from air into water? h(z)b qf/pk t;hh .yd3

  The effect of a double slit on monochr6fn 7f up5-xq 2h. 0pg4lwegtuomatic light is observed by the set up in ttpuh4n 5p lu6g0f2gqwf x7.e- he diagram below.



Interference fringes are seen on the screen.

Which of the following changes would increase the distance between the adjacent fringes?

  This diagram below shows two apertures through which planar waves au.3ih) gob ,iyre passed as they are moving to the left. The wavefronts show crests moving in phase. Given this information, at which point will the amplitude of y g.uiob)3ih, the waves be a minimum?



A flat plate made of glass has a refractive index of $n=1.52$. What is the speed of light within this material?

  Diamonds are highly valued because ofldwdue(53 uh 9 their sparkle. This is caused by total internal reflection, which reflects most of the light that falls onto a cut diamond out of the face we see. Fake gems, called 'paste', are often used in jewellery because they are cheaper. However, paste gems sparkle mdhedu( 3 5ulw9uch less than real diamonds.

The diagrams show a possible path of light through a real diamond, and another through a fake.



If:

- $n=$ refractive index;

- $n_{d}$ is the refractive index of the diamond

- $n_{f}$ is the refractive index of the fake

- $v=$ speed of light

- $v_{d}$ is the speed of light in the diamond

- $v_{f}$ is the speed of light in the fake

Which row in the table contains only statements which must be true?

  When moving from mater)8 *9jyhp9e tzcg e;bsial $A$ to material $B$, the direction of a ray of light moves away from the normal. If $n_{A}$ and $n_{B}$ are the refractive indices of materials $A$ and $B$ respectively, then which of the following statements is true in this situation?

  When a light ray enters a denser medium and refracts, some of tol7, ;qoy+sck he characteristics of the wave will change. Which of the following options is correct about toy,l7 qsk oc;+his change?

  Young's double-slit experiment 3mpjskito,0h gt*)ng0/* (x3jgw dpp is setup as shown, including a monochromatic source, a single slit, a double slit and a screen. What is the purpose of the single slit in this experimengkpms3w0g *h n3pxptd j0 )i( *tg,j/ot?

  Our fingerprints are made up of a series of ridges on the end of the fer35u lw2/h miinger. These ridges can be 'reu/m h5wi3 2rlead' by electronic devices.

The diagram below shows a certain type of fingerprint detector below, which works by scattering light when pressure is applied to a plastic screen. The ridges of the fingerprint press the plastic film against the glass when the finger is pressed to the screen.




When not in use, the plastic screen and the glass have a small air space between them. The diagram below shows the two possible paths for the light when the finger is pressed down.




Which row in the table correctly describes the properties of the fingerprint detector that cause the bright and dark patches on the image produced by the camera?

  The diagram shows a wave apy976-jlh k tk4plr( zpproaching an aperture.


Which diagram correctly shows the resulting diffraction pattern for the wave?

  The diagram shows two waves. One wave is emiru k hrdskr6rmzd4-;2:url6 0tted from source $s_{1}$ and travels to point $P$. The other wave is emitted from source $s_{2}$ and travels to point $P$.



What is the path difference between the waves?

  Two waves from individual point sources meet at qb)n yh4ltp )9k* -zeea point $X$. Which of the following conditions is necessary for stable interference pattern to be observed at point $X$ ?

  The double-slit equation describes the relationship between t4ax67)k1cc kh ee0 hehhe separation distance of the fringes on the screen, s, the distance between the screen and the slitskc74 he)exkh60ec a1h, $D$, the separation of the slits, $d$, and the wavelength, $\lambda$, of the light.

$$
s=\frac{\lambda D}{d}
$$

Which line gives the correct units for the quantities?

  Identical waves that begin propagation at thmqi d gn9u413jq95i s,v,vpdb e same time leave from two different sources and arrive at th,d3id9i j ,5vbn9 mqugv4qs1pe same point point $X$. The first source is $18 \mathrm{~m}$ from point $X$. The second source is $10.5 \mathrm{~m}$ from point $X$. The waves of both sources have a wavelength of $3 \mathrm{~m}$. What is observed at $X$ ?

  Which of the following options willr iigu)k ,-w6b alter the frequency of a wave?

  A ray of light is incident on a material made from thrx 2 x3kq8j(p 4zb,jl aig/4yrxee layers, each having a different optical density, so that in each layer the light travels at a r ,lj( gi2/j3kzqx8xa p44xybdifferent speed.

- For layer 1: refractive index $=n_{1}$ and the speed of light $=c_{1}$

- For layer 2: refractive index $=n_{2}$ and the speed of light $=c_{2}$

- For layer 3: refractive index $=n_{3}$ and the speed of light $=c_{3}$

- Angle of incidence $=i$

- Angle of refraction $=r$

This is illustrated in the diagram below:




Which is the correct expression for $c_{3}$, the speed of light in the thirdlayer?