Scientists test three new materials, A, B and C.
They direct ultraviolet, visible light and infrared at a 5 mm thick sheet of each material and measure the percentage of each radiation transmitted.
Table
| Material | Ultraviolet transmitted in %\%% | Visible light transmitted in %\%% | Infrared transmitted in %\%% |
|---|---|---|---|
| A | 2 | 90 | 85 |
| B | 75 | 88 | 10 |
| C | 0 | 0 | 70 |
Identify the material that would be best for the lenses of sunglasses that protect the eyes from ultraviolet. Give a reason for your answer.
A television contains a sensor that detects infrared signals from a remote control. The sensor is behind a cover made from material C.
Explain why material C is suitable for the cover.
State what the data shows about the way different substances interact with electromagnetic waves.
For material B, 5% of the infrared is reflected.
Calculate the percentage of the infrared that is absorbed by material B.
84 exam-style questions on Edexcel GCSE Physics 5.2 The electromagnetic spectrum, covering 5.2.1 Electromagnetic waves and refraction in glass (core practical), 5.2.2 Groups of the electromagnetic spectrum, 5.2.3 Wavelength-dependent behaviour of EM waves, and 5.2.4 Velocities of EM waves in different substances. Each one has a worked solution and a mark scheme showing where the marks go.