Chapter Questions
What phenomenon does the diagram below demonstrate?A diffractionB interferenceC reflectionD refraction(FIGURE CANT COPY)
Explain how the width of a double-slit interference pattern would change if all the variables were constant but a blue laser was replaced with a green laser.
Polarisation is an important phenomenon. What does it show about light?A It can travel instantaneously at an infinite speed.B It travels faster in materials like water and air than in a vacuum.C It is a longitudinal wave.D It is a transverse wave.
Explain briefly why snowboarders and sailors are likely to wear polarising sunglasses.
Red light $\left(4.5 \times 10^{14} \mathrm{~Hz}\right)$ has a wavelength of $500 \mathrm{~nm}$ in water. Calculate the speed of red light in water.
Choose the correct answers from those given in bold to complete the following sentence about refraction. As light travels from quartz $(n=1.46)$ to water $(n=1.33)$, its speed increases/decreases which causes it to refract away from/towards the normal.
The figure represents a situation involving the refraction of light. Identify the correct label for each of the lines from the choices provided: boundary between media, reflected ray, incident ray, normal, refracted ray.(FIGURE CANT COPY)
The speed of light in air is $3.00 \times 10^8 \mathrm{~m} \mathrm{~s}^{-1}$.As light strikes an air-perspex boundary, the angle of incidence is $43.0^{\circ}$ and the angle of refraction is $28.5^{\circ}$. Calculate the speed of light in perspex.
A ray of light travels from air, through a layer of glass and then into water as shown. Calculate angles $a, b$ and $c$.(FIGURE CANT COPY)
A ray of light exits a glass block. On striking the inside wall of the glass block, the ray makes an angle of $58.0^{\circ}$ with the glass-air boundary. The index of refraction of the glass is 1.52 . Calculate the:a angle of incidenceb angle of refraction of the transmitted ray (assuming $n_{\text {air }}=1.00$ )c angle of deviationd speed of light in the glass.
A narrow beam of white light enters a crown glass prism with an angle of incidence of $30.0^{\circ}$. In the prism, the different colours of light are slowed to varying degrees. The refractive index for red light in crown glass is 1.50 and for violet light the refractive index is 1.53 . Calculate the:a angle of refraction for the red lightb angle of refraction for the violet lightc angle through which the spectrum is dispersedd speed of the violet light in the crown glass.
Calculate the critical angle for light travelling between the following media.$$\begin{array}{|l|l|}\hline \text { Incident medium } & \text { Refracting medium } \\\hline \text { ice }(n=1.31) & \text { air }(n=1.00) \\\hline \text { salt }(n=1.54) & \text { air }(n=1.00) \\\hline \text { cubic zirconia }(n=2.16) & \text { air }(n=1.00) \\\hline\end{array}$$abc
When a light ray refracts, the difference between the angle of incidence and angle of refraction is known as the angle of deviation. Sort the following boundaries between media in order of increasing angle of deviation.A water $(n=1.33)$ to diamond $(n=2.42)$B water $(n=1.33)$ to air $(n=1.00)$C air $(n=1.00)$ to diamond $(n=2.42)$D glass $(n=1.50)$ to air $(n=1.00)$
Light of an unknown wavelength emitted by a laser is directed through a pair of thin slits separated by $75 \mu \mathrm{m}$. The slits are $4.0 \mathrm{~m}$ from a screen on which bright fringes are $3.1 \mathrm{~cm}$ apart.a Calculate the wavelength of the laser light in $\mathrm{nm}$.b Identify the unknown colour emitted by the laser.
The following diagram shows the resulting intensity pattern (simplified) after light from two slits reaches the screen in a double-slit experiment. Copy the diagram into your workbook and circle the points at which the path difference is equal to $1 \frac{1}{2} \lambda$.(FIGURE CANT COPY)
Arrange the types of electromagnetic radiation below in order of decreasing wavelength.gamma rays, visible, microwaves, radio waves, $\mathrm{X}$-rays, infrared, ultraviolet
What form of electromagnetic radiation is used in the following applications?a mobile phone communicationb night-vision gogglesc medical imaging
An AM radio station has a frequency of $612 \mathrm{kHz}$. If the speed of light is $3 \times 10^8 \mathrm{~m} \mathrm{~s}^{-1}$, calculate the wavelength of these waves to the nearest metre.
Describe Young's experiment and explain why it is considered evidence for the wave theory of light.
Explain briefly why a microwave oven is tuned to produce electromagnetic waves of a particular frequency.