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 monochromatic laser beam is shone into the surface of a tank filled wi *;k:cb( ivrmi48ywxi th water. The efkirvibw(:i 4m8x ;*yc fects on the laser beam due to the water are observed.

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

  Which property of a wave does not change aen bq;4lde.w4s a result of refraction?

  Diamonds are highly valued becausenw xzx0ec5v( 0 of their sparkle. This is caused by total internal refl0 (nzwx 0ce5xvection, 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 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?

  The diagram below shows an arrangement used to investije3 dkr5pupx,uyo+)+ gate double slit interference using mkyu 3jr dep5o+ x)p,u+icrowaves.



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.

  A double slit interference experiment is conducted using monyqj 9m;fh 9qyz.but up,n f8:6ochromatic light of wavelengm:p8 .t9ff6jun u qybz, yh9q;th $\lambda$. 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 sent4 mxr z+ui l-m-q5ayg0ence?

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

  This diagram below shows two apertures through which planb8h8p +qh/7na+ nq jmfva) -viar waves are passed as they afb-+jvmh88na7qp/ a)hiv+qn re moving to the left. 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?

  Which of the following imagmaa-66nv-ithz8jrhxt) . w h 0es shown below best represents the path of visible light traveling through a glawta 6hxr-a-v j6z 8.h h0tn)imss prism?

  The diagram shows a wave apyb*z6tx vu1bhyzb 3q6q ;,6iy)gwas 1proaching an aperture.


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

  $\mathrm{K}$ 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?

  The effect of a double slit on monochromatic light is observed by the set up ih ), h .ixvas0gd guypg74aedil31t8-n the diagram belp0 udvy ltgaae-x47 h8, d3gigsh.i 1)ow.



Interference fringes are seen on the screen.

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

  In a Young's double-slit e3my87 aatz+kcq 9s f/gxperiment, the 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 $s$ ?

  Young's double-slit experiment is setup as shoq;82k3+z*o lu,;c85ew t6 zfrj fwalg5r fei nwn, including a monochromatic source, a single slit, wt3 i8 k zqwff2*fae;oj clneuz+ g,rr6l8 5;5a double slit and a screen. What is the purpose of the single slit in this experiment?

  A ray of light is incident on a material made from three layers, each 0 +.c qqs ybq-w0kc2mrmy;9w/e hf5lvhaving a different optical density, so that in each layer the light travels at a different s;0h m 9qely cy5fkb2qwm-c.qv0 rw /+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?

  A student is investigating the interference tu -zwd3)c2cq;v pl;kdq yz0 er 70-eeof waves. They set up coherent waves -;-2 zl7qdc;t ec v)e 3 p0rydukz0eqwproduced 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?

  Which image shows the correct ray diagram for light passing fro*to : -guqn-k67 tgbnakm53njm air into water?na t * -tqnbjug35gkmon6-:7k

  The double-slit equation describes the relationship between the separatiof hfq6.- a1huyqld+*cn 08euqn distance of the fringes on the screen, s, the distance between the screen andd *q q.a81cy6 -0nulhfequ h+f 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?

  Which of the following options will alter the frequency of3g0y/f utu k/e a wave?

  When does diffraction sb9- :b7kv*3kwjn n faoccur?

  Which row correctly describes the conditions for const7ogypus (0hm 1ructive and destructive interfereg yo1u0 mps(h7nce in a double-slit diffraction pattern?

  Ray diagrams can be used to show the refl4 u;pqh gc6xn7k 08gnfection, refraction and transmission of light at the boundary between media. 7;x4hfguqc 0g n6np8k


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

  Identical waves that begin propagation at thezrye 4ps;*2ih d8m1n-2lasyb wov; 0t same time leave from two different sources and arrive at the same ;bptv-yi2d 4hsn ; ozlasr1*myw 08e2point 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 $X$ ?

  Our fingerprints are made up of a series of ridges on the end of the finger. le .;wqo4ak09vl cu (xThese ridges can be 'read' by eo9qvwc(u x4el;. lk0alectronic 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 two waves. One fphrk:p7q g(jz 9*0p0mieh l +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 enters a denser medium +p3h 0 p1bhsifxd/ )f ur)ty7yand refracts, some of the characteristics of the wave will change. W0tf) 3 / y)shxrh1p+ubfdpiy7hich of the following options is correct about this change?

  Two waves from individual po*rz k+us5 to2,ji/kjuyqh3 ;uint sources meet at a point $X$. Which of the following conditions is necessary for stable interference pattern to be observed at point $X$ ?

  When moving from matqwb vvf1 8m)3 9p,h7;ykk wbpeerial $A$ 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?