23-30 SUMMARY AND QUIZ

14. Why do warm objects, such as humans and warm-blooded animals, stand out on thermal images against cooler backgrounds? Infrared radiation X-rays Visible light

Answer infrared radiation

27. Waves A and B both travel at the same speed. If Wave A has a frequency of 100 Hz (meaning, 100 per second) then what, approximately, is the frequency of Wave B? If Wave A has a frequency of 100 Hz (meaning, 100 per second) then what, approximately, is the frequency of Wave B? 200 Hz 11 Hz 100 Hz 50 Hz

Answer; 200 Hz

35. Which set correctly lists colors of light in order of increasing wavelength? Blue, red, green Red, blue, green Red, green, blue Blue, green, red

Answer; Blue, green, red

39. Which statement explains why it might take several seconds after lightning strikes before thunder is heard? Light is faster than sound. Light has more energy than sound. Light travels in a vacuum.

Answer; Light is faster than sound.

33. If an electromagnetic wave's wavelength is equal to the diameter of Earth, which kind of electromagnetic wave is it? X-ray Microwave Gamma ray Radio wave

Answer; Radio wave

31. Which statement BEST describes why the sound produced by a major explosion on the moon would never be heard on Earth? Sound waves have too long of a wavelength to travel through space. Sound waves require a medium to transport their energy. Sound waves have too low of a speed to travel that far a distance. Sound waves have too small of an amplitude to carry the sound to Earth.

Answer; Sound waves require a medium to transport their energy.

37. Which kind of electromagnetic radiation is likely to cause a nasty sunburn if you do not use sunscreen at the beach? Infrared Ultraviolet Visible light Radio waves

Answer; Ultraviolet

18. What is the most penetrating radiation? Microwave X-ray Ultraviolet

Answer; X-ray

36. Electromagnetic radiation travels as waves, and the amount of energy it delivers when absorbed by matter or the damage it can cause depends on its wavelength. Which kind of light delivers the most energy and is the most damaging? Infrared X-rays Microwaves Radio waves

Answer; X-rays

24. Review the image of the coiled spring. As the end of a coiled spring is moved back and forth along the direction of the spring, which kind of wave travels along the coiled spring? A transverse wave A longitudinal wave

Answer; a longitudinal wave

25. Review the image of the coiled spring. As the end of the coiled spring is moved up and down, which kind of wave travels along the coiled spring? A transverse wave A longitudinal wave

Answer; a transverse wave

15.Which property of a sound wave determines its loudness? Wavelength Amplitude Frequency

Answer; amplitude

20. What determines the amount of energy a sound wave carries from a loudspeaker to a listener's ear? Direction Wavelength Amplitude Frequency

Answer; amplitude

12. Which statement describes amplitude? Amplitude is the distance between the equilibrium and trough. Amplitude is the distance between two adjacent crests. Amplitude is the distance between the crest and the trough.

Answer; amplitude is the distance between the equillibrium and trough.

22. What are microwaves commonly used for? Tumor treatment Cell phone communication Reading illumination Medical imaging

Answer; cell phone communication

40. A train traveling 50 mph slows down and stops once the brakes are applied. The train's kinetic energy _____. is conserved. becomes stored in the train's engine. changes to the thermal energy of the brakes.

Answer; changes to the thermal energy of the brakes.

13. What are radio waves commonly used for? Medical equipment Disease treatment Communication

Answer; communication

6. A sound wave is a propagation of wavelengths and compressions. wavelengths and expansions. compressions and expansions.

Answer; compressions and expansions

5. Regions where the particles of a medium are farther apart are called compressions. expansions.

Answer; expansions

16. Which property of a sound wave determines pitch? Amplitude Frequency Wavelength

Answer; frequency

19. Suppose you produce a wave that travels along a long coiled spring by repeatedly moving the end of the spring back and forth along the direction of the spring. If you increase the number of times you move the end of the spring back and forward per second, but the speed of the wave stays the same, you increase the _____________. amplitude wavelength frequency

Answer; frequency

17. What is the most energetic radiation? Radio waves Infrared radiation Gamma rays

Answer; gamma rays

21. Which type of electromagnetic radiation has the highest frequency? Blue light Radio waves Infrared Gamma rays

Answer; gamma rays

10. Which frequency does a shorter wavelength correspond to at constant speed? Higher frequency Lower frequency

Answer; higher frequency.

1. In which situation can a sound wave propagate? If the medium is in a vacuum If the medium is air If the medium is water If particles of a medium are present

Answer; if particles of a medium are present

2. What accurately describes a sound wave? It is both the motion of particles and a disturbance away from the source of sound. It is a disturbance that moves through a medium away from the source of sound. It is a transverse wave. It is the motion of particles of the medium away from the source of sound.

Answer; it is a distrubance that moves through a medium away from the source of the sound

34. If you are told the wavelength of the light emitted by a laser, what could you infer about that light? Its color Its speed in a vacuum Its amplitude Its intensity

Answer; its color

9. Which statement about light is correct? Light is not a wave. Light travels more slowly than sound in air. Light travels faster than sound.

Answer; light travels faster than sound.

4. You and a friend are holding a coiled spring stretched between the two of you. If you push your end toward your friend and then pull it back toward you, a _____ wave will be created in the coiled spring. longitudinal transverse

Answer; longitudinal

7. What is the best description of frequency? Number of oscillations per second Measure of how compressed or expanded the medium becomes

Answer; number of oscillations per second

23. Which kind of electromagnetic radiation is commonly used for controlling air traffic by locating planes? Ultraviolet Radio waves X-rays Visible light

Answer; radio waves

41. When energy changes from one type to another, the total energy ____. remains constant. is lost. is gained.

Answer; remains constant.

38. Which statement describes sound waves? Sound is a traverse wave. Sound is a longitudinal wave. Sound can travel in a vacuum.

Answer; sound is a longitudinal wave.

8. In an old cowboy movie, a cowboy presses his ear to the ground, listening for the sound of approaching horse hooves. Why does the cowboy listen through the ground and not the air? Sound waves travel faster through the ground. Sound waves are affected by temperature. Sound waves are louder through the air.

Answer; sound waves travel faster through the ground.

26. Which characteristic distinguishes a longitudinal wave from a transverse wave? The direction of the wave's vibration The speed at which the wave travels The frequency of the wave's vibration The amplitude of the wave's vibration

Answer; the direction of the wave's vibration

11. While listening to someone playing a piano, you observe that he hits a key gently. Moments later, he hits the same key again but much harder this time. In the second case both loudness and pitch stay the same. the loudness has increased, but the pitch has stayed the same.

Answer; the loudness has increased, but the pitch has stayed the same.

30. How does a sound wave carry energy from a loudspeaker to the ear of the listener? Air currents move with the sound to carry the vibrating molecules to the listener. The vibrating molecules move from the speaker to the ear of the listener. The pattern of compressions travels; the air itself remains in about the same place.

Answer; the pattern of compressions travels; the air itself remains in about the same place.

28. Deep ocean waves carry energy long distances across the ocean. Review the following image and determine how the wave carries the energy it needs to move the life preserver from a long distance. How does the wave carry the energy it needs to move the life preserver from a long distance? The wave pattern travels along the water without carrying the water itself very far. The ocean currents carry the moving water to the life preserver. The entire ocean moves back and forth to create energy. The wind that causes the waves also moves the life preserver.

Answer; the wave pattern travels along the water without carrying the water itself very far.

29. When one end of a long rope is secured in a stationary spot and you move the other end of the rope up and down, you will create waves in the rope. Those waves carry energy. How is the energy that is carried along the length of the rope a wave? Vibrations in the air and surroundings carry the energy of the rope. A longitudinal compression wave moves down the rope. The entire rope moves back and forth together. The waveform travels along the rope without each small segment of rope moving very far.

Answer; the waveform travels along the rope without each small segment of rope moving very far.

3. The horizontal distance after which a wave repeats itself in space is called the wavelenth. amplitude.

Answer; wavelength

32. A difference in which of the following characteristics distinguishes radio waves from X-rays? Speed Wavelength Ability to travel in a vacuum Amplitude

Answer; wavelength