15.1 The Electromagnetic Spectrum
Describe one way in which heat waves—infrared radiation—are different from sound waves.
- Sound waves are transverse waves, whereas heat waves—infrared radiation—are longitudinal waves.
- Sound waves have shorter wavelengths than heat waves.
- Sound waves require a medium, whereas heat waves—infrared radiation—do not.
- Sound waves have higher frequencies than heat waves.
15.2 The Behavior of Electromagnetic Radiation
Describe what happens to the path of light when the light slows down as it passes from one medium to another?
- The path of the light remains the same.
- The path of the light becomes circular.
- The path of the light becomes curved.
- The path of the light changes.
How many lumens are radiated from a candle which has an illuminance of 3.98 lx at a distance of 2.00 m?
- 400 lm
- 100 lm
- 50 lm
- 200 lm
Saturn is 1.43×1012 m from the Sun. How many minutes does it take the Sun’s light to reach Saturn?
- 7.94 × 109 minutes
- 3.4 × 104 minutes
- 3.4 × 10–6 minutes
- 79.4 minutes