Table 1 below shows part of the electromagnetic spectrum.
Table 1
| Gamma rays | Microwaves |
Complete Table 1 with the rest of the electromagnetic spectrum
Use the correct answers from Figure 1 to complete the sentence.
Figure 1
| amplitude | frequency | speed | wavelength |
From left to right, the electromagnetic spectrum in Table 1 is ordered from increasing ......................... and decreasing ........................
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Some forms of electromagnetic (EM) radiation can be dangerous.
Complete the sentences.
Choose answers from the box.
Each answer can be used once, more than once or not at all.
| a larger | a smaller | the same |
EM radiation with .............................. wavelength has a lower energy.
Higher energy EM radiation poses .............................. danger compared to lower energy EM radiation.
Higher energy EM radiation travels at .............................. speed compared to lower energy EM radiation.
Microwave ovens are designed to heat up food.
However, they cannot heat up completely dry food.
Explain why.
Visible light passes through a glass window.
Which two main processes does the visible light undergo?
Tick (✓) two boxes.
| Transmission | format('truetype')%3Bfont-weight%3Anormal%3Bfont-style%3Anormal%3B%7D%3C%2Fstyle%3E%3C%2Fdefs%3E%3Ctext%20font-family%3D%22stix8ea284a28ff5a7e227709c23200%22%20font-size%3D%2236%22%20text-anchor%3D%22middle%22%20x%3D%2218.5%22%20y%3D%2237%22%3E%26%23x25A1%3B%3C%2Ftext%3E%3C%2Fsvg%3E) |
| Absorption | format('truetype')%3Bfont-weight%3Anormal%3Bfont-style%3Anormal%3B%7D%3C%2Fstyle%3E%3C%2Fdefs%3E%3Ctext%20font-family%3D%22stix8ea284a28ff5a7e227709c23200%22%20font-size%3D%2236%22%20text-anchor%3D%22middle%22%20x%3D%2218.5%22%20y%3D%2237%22%3E%26%23x25A1%3B%3C%2Ftext%3E%3C%2Fsvg%3E) |
| Reflection | |
| Refraction | |
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Figure 1 shows the path of light travelling through a block of glass.
Figure 1
State the name of the process in Figure 1.
On Figure 1, draw the normal at the points where the light enters and leaves the glass.
Label both angles of incidence on Figure 1.
Describe how the frequency, wavelength and wave speed change as the light passes from the air to the glass.
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Figure 1 shows the apparatus that a student used to investigate the heating effect of different wavelengths of light.
Figure 1
The student put thermometer D outside of the light spectrum.
Suggest why.
Table 1 gives the position and reading of each thermometer 10 minutes after the investigation started.
Table 1
| Thermometer | Position of thermometer | Temperature in oC |
| A | in violet light | 21 |
| B | in green light | 22 |
| C | in red light | 24 |
| D | outside the spectrum | 20 |
Summarise the results of Table 1, referring to wavelength in your answer.
A similar investigation completed in 1800 by the scientist Sir William Herschel led to the discovery of infrared radiation.
Suggest how the student could show that the spectrum produced by the glass prism has an infrared region.
A thermal imaging camera detects infrared radiation. Electronic circuits inside the camera produce a visible image of the object emitting the infrared radiation.
At night, police officers use thermal imaging cameras to track criminals running away from crime scenes.
Thermal imaging cameras work better at night than during the day.
Explain why.
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When metal is exposed to infrared radiation, its temperature increases and it emits visible light.
In terms of photons and energy levels of the metal atoms, explain why visible light is emitted.
As the metal receives higher energy infrared radiation, it becomes hotter and the visible light emitted changes from red to yellow.
Suggest why the colour changes.
Higher energy electromagnetic radiation is dangerous and is often described as "ionising radiation".
Explain why it has this name.
The scientific unit of measurement used to measure the dose received from radiation, such as X-rays or background radiation, is the millisievert (mSv).
Table 1 shows the X-ray dose resulting from CT scans of various parts of the body.
Table 1 also shows the time it would take to get the same dose from background radiation.
Table 1
| Part of the body | X-ray dose in mSv | Time it would take to get the same dose from background radiation |
| Abdomen | 9.0 | 3 years |
| Sinuses | 0.5 | 2 months |
| Spine | 4.0 | 16 months |
A student suggests that the X-ray dose and the time it would take to get the same dose from background radiation are directly proportional.
Use calculations to test this suggestion and state your conclusion.
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Table 1 shows information about the electromagnetic spectrum.
Table 1
| Radio | Micro-wave | Infra-red |
Visible light |
Ultra-violet | X-rays | Gamma-rays | |
| Frequency | 3MHz | 30GHz | 3THz | 3000THz | 3000000THz | 300000000THz | |
| Wavelength | 100m | 1cm | 100μm |
Show that the speed of electromagnetic radiation is 3 × 108 m/s, then calculate the wavelength of these ultra-violet waves in nm.
Give your answer to 2 significant figures.
Wavelength (2 significant figures) = .................................... nm
Ultra-violet waves can damage human skin.
Describe the damage caused to human skin by ultra-violet waves.
Sun cream can be used to protect skin from ultra-violet waves. Sun creams have different sun protection factors (SPF).
Figure 1 shows the information written on the back of a bottle of sun cream.
Figure 1
|
This sun cream has a SPF of 10. |
A doctor says ‘adults should not sunbathe for more than 20 minutes in the midday sunshine when not using sun cream’.
If an adult used sun cream with SPF 6, calculate how long they could safely sunbathe for.
Ultrasound and X-rays are used to scan patients in hospital.Table 1 contains information about these two different waves.
Table 1
| Name | Frequency | Wavelength | Type | Description |
| Ultrasound | ≥ 2MHz | ≤ 1.6 × 10 -4m | Longitudinal | Pressure soundwave |
| X-rays | ≥ 3 × 1016Hz | ≤ 10nm | Transverse | Electromagnetic wave |
Ultrasound and X-rays are used to scan different parts of the patient.
Explain how ultrasound and X-rays are used and evaluate the risks and benefits of using these two different waves to scan patients in hospital.
Use the information in the table in your answer.
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Radio waves are detected using metal antennae.
What happens when an antenna absorbs radio waves?
Describe how radio waves are different from gamma rays.
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Figure 1 below shows an X-ray image of a human skull.
Figure 1
When X-rays enter the body, what does the following do to the X-rays?
(i) Soft tissue
(ii) Bone
X-rays are used in hospitals for computed tomography (CT) scans.
Give two other medical uses for X-rays and state a property of X-rays that makes them useful for these.
Table 1 below shows the total dose of X-rays received by the human body when different parts are X-rayed.
Table 1
| Part of body X-rayed | Dose of X-rays received by human body in arbitrary units |
| Chest | 4 |
| Pelvis | 60 |
| Head | 3 |
Calculate the number of chest X-rays that are equal in dose to one pelvis X-ray.
Stars emit all types of electromagnetic waves. However, an X-ray telescope on Earth is unable to detect X-rays emitted from distant stars.
Explain why this is the case and give a solution to this problem.
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Light changes direction as it passes from one medium to another.
State the name of this phenomena and explain why this happens.
Figure 1 shows a light ray changing direction as it passes from air into a glass block.
Figure 1
Draw a light ray coming out of a glass block.
State the direction of the light ray in part (b) and why you have drawn it this way.
What property of the light does not change when it passes from the air to the glass block?
Explain why this is the case.
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A student carried out an experiment to test how the colour of an object affects the amount of blackbody radiation emitted by that object.
The student took two identical flasks and painted one of them black and the other silver, as shown in Figure 5 below
Figure 5
The plan was to fill them both with hot water and then measure how their temperatures changed over time.
Suggest two other things that the student should have done in order to ensure a fair test.
The graph in Figure 6 below shows the students results for the silver flask.
Figure 6
Add another line to the graph in Figure 6 showing the results you'd expect the student to get for the black beaker.
After leaving the silver flask for a long period of time, the temperature of the beaker finally settled at 20 degrees Celsius.
Explain what is significant about this temperature.
How would the final temperature of the black flask compare to the temperature of the silver flask?
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