# Glencoe Science Level Blue

## Chapter 22: Electricity

### Standardized Test Practice

 1 Which of the following terms refers to the change in direction of a wave when it travels from one material into another? A) refraction B) diffraction C) reflection D) transmission 2 The table shows the speed of sound through different materials. About how far can sound travel in air in 1.45 s if the air temperature is 20°C? [insert art 681_STP_Questions_ta01 table of speed of sound, p. 720] A) 237 m B) 423 m C) 721 m D) 497 m 3 Sound travels 8,740 m through a material in 5.7 seconds. What is the material? [insert art 681_STP_Questions_ta01 table of speed of sound, p. 720] A) glass B) steel C) seawater (25°C) D) water (25°C) 4 Which of the following is true about light waves? A) They travel at the same speed through matter and empty space. B) They cannot travel through matter. C) They slow down when traveling through matter. D) They are a type of compressional wave. 5 Which of the following shows a trough of the wave in the figure? (15.0K) A) label H B) label F C) label G D) label J 6 Which label shows the amplitude of the wave? (15.0K) A) label G B) label F C) label H D) label J 7 What is the highest frequencies of sound that humans can hear? A) 150 Hz B) 200 Hz C) 5000 Hz D) 20,000 Hz 8 If the intensity of a sound increases by 30 dB, by what factor is the energy carried by the sound wave increased? A) 30 times B) 100 times C) 300 times D) 1000 times 9 You hear thunder 2.5 seconds after you see a lightning flash. Later you hear thunder 2.0 seconds after you see a flash. If the sound travels at 340 m/s, how much closer was the second lightning strike than the first one? A) 170 m B) 850 m C) 680 m D) 1530 m 10 The frequency of a sound is 43.6 Hz, and the sound travels through air at 343 m/s. What is the wavelength of the sound? A) 7.87 m B) 1.80 m C) 127 m D) 2700 m