A monochromatic laser beam is shone into the surface i26xvn 1g f5n2r71eu1 oauuobof a tank filled with water. The effects on theu2o xou g2n evfr171a5ni61 bu laser beam due to the water are observed.

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

  A student is investiga:wro8 vz6b8ii w8pp( cting the interference of waves. They set up coherent waves produce ip 8 68vz8b(piwwo:crd 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?

  $\mathrm{K}$ 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?

  A ray of light is incident on a material made from three layers, each havgu g doyio1.258 *ypxjing a different optical density8po 1*x5gjy go.2 ydui, so that in each layer the light travels at a different 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?

  When does diffraction occur? .iw/+i-a)y qs:vl+*6ino;jhnr gogm

  The double-slit equation describes the ;n9c vwk,3ntpc +tcc8relationship between the separation distance of the fringes on the screen, s, the distance between the screet,8n + v;tnpcw93k cccn and the slits, $D$, 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?

  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?

  Ray diagrams can be used to show the reflection, refractio )qrli7n2d (qvn and transmission of (2l di vrnq7q)light at the boundary between media.


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

  In a Young's double-slit experiment, tz :m7ag8yitx )s bu9n(he spacing of the double slits 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 $s$ ?

  The diagram below shows an arrangement usey7 8ns)gopzkd3e* 34 ; rgut)v wkx8rnd to investigate double slit interference usinvgztr; d 3nek 74wp8y*o u gn)sk8rx3)g 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.

  Two waves from individut,2p dij2,hlc al point sources meet at a point $X$. Which of the following conditions is necessary for stable interference pattern to be observed at point $X$ ?

  Which row correctly describes the conditions foc4k,gaa. 8/szihwqw,r constructive and destructive interference in a double-slit diffraction 4i8/ hc,,wqzkw as ga.pattern?

  The diagram shows twr3 :ubox*x7e mo waves. One wave is emitted 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?

  When a light ray entyqo p.u;:xo rzauwx9pr+/ o9bc*x2+v ers a denser medium and refracts, some of the characteristics of the wave will change. Which of the follxoyz .pour ; +rxx9 wpv/a 9ub+qo2*c:owing options is correct about this change?

  This diagram below shows two apert+m +gd u4lpkj*0 *dditures through which planar waves are passed as they are moving to the leftkm +l0d* * +idu4jdgtp. The wavefronts show crests moving in phase. Given this information, at which point will the amplitude of 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?

  The diagram shows a wave approaching an aperx gxce68e3k ym:i.o j*ture.


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

  Which of the following images shown below best repreqe3kfplcrmy g5 )9y6(sents the path of visible light traveling through a glass prismf6 cmre q9gk)l(y5yp3?

  Our fingerprints are made up of 5l*v/ef3gkzx :f2ltm1 ek6ne a series of ridges on the end of the finger. These ridges can be 5 kkm e/t:z26 fnl*xl 1egvef3'read' 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?

  When moving from materl3gn /0mm) w+h1nctwm ial $A$ 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?

  Which image shows the correct ray diagram for light pasaun o, lc:zz38sing from air into water? l:z oa8,n3z uc

  Which property of a wave doesff 5 /3krcztto9rm)5i not change as a result of refraction?

  Diamonds are highly valued because of their sparkle. This is caused by total inll 2n1w5v*gyk*g as18oy 3ewiy y .mx:ternal reflection, which reflects most of the light that falls onto a cut diamond out ofvly:nyy l1 wge* mo2w*8gx.k asiy 351 the face we see. Fake gems, called 'paste', are often used in jewellery because they are cheaper. However, paste gems sparkle much 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?

  Identical waves that begin proqvf uoo)q n2qpbse5t3/ ,x85mpagation at the same time leave from two different sources and arrive xeufo o25)v ,q5sq8bnq3tm p/at the 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 $X$ ?

  The effect of a double slit on mvp6kdw h0(5ou onochromatic light is observed by the set up in the diagram below.h5d w0(op6kv u



Interference fringes are seen on the screen.

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

  Which of the following options will alter the frequency 9mf xdjx o(r)0of a wave?

  Young's double-slit experiment is setup as shown, including a monochrod wul1 km;vw ynp1pd9m(f71 *jm 5vi(amatic source, a single slit, a double slit and a screen. What i pnlammpy ;dw19umfk15j(v1d( 7wi *vs the purpose of the single slit in this experiment?

  A double slit interference experim 6g; *b *ouo.tumh:aomgh*d8sent is conducted using monochromatic light of wavelength h m as*hd*gtou ob;.u6:g*8mo$\lambda$. 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 phrase correctly completes the following sentence?1wr(q+ em6rsiy9srd 3

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