Figure 1 shows the wavelengths of some types of electromagnetic radiation.
Suggest one device or material that can be used to detect infrared radiation.
Which of the following values is a wavelength of green light?
- 320 nm320\text{ nm}320 nm
- 420 nm420\text{ nm}420 nm
- 530 nm530\text{ nm}530 nm
- 740 nm740\text{ nm}740 nm
An industrial optical sensor can detect electromagnetic radiation with wavelengths between 320 nm320\text{ nm}320 nm and 1050 nm1050\text{ nm}1050 nm. Give two ways the radiation detected by this sensor is different from the radiation detected by human eyes.
Complete the sentences. Choose the answers from the box:
| absorbed | emitted | reflected | refracted |
When sunlight shines on a green leaf, the green light is ____________.
All other colours of light shining on the green leaf are ____________.
A student looks at the green leaf through a red filter. How does the leaf appear to the student?
- Black
- Green
- Red
- Yellow
The student also looks at their reflection in a crumpled, rough piece of aluminium foil. What type of reflection happens at this rough surface?