Part A-Multiple Choice. Choose the best answer. One mark each. (5 marks) 1) A car has a loose bolt, with a natural frequency of 5.0 Hz. It vibrates when one of the wheels gives the car a bump, once each rotation. If the radius of the tire is 36 cm, what is the car's speed when the bolt vibrates? a) 7.2 cm/'s b) 45 cm/'s c) 5.7 m/s d) 11 m's 2) The speed of any wave as it propagates through a medium is dependent mainly on the: a) frequency b) wavelength c) period d) medium 3) Which of the following correctly describes the changes that occur in a sound wave, as it passes from cool air into warmer air? a) v, ). and f increase b) v, ) and f decrease c) v and ) increase d) v and a decrease 4) The sound of a whistle used in sports has a warbling sound produced by beats. If the frequency of the whistle is about 5.0 kHz, what other frequency would most likely be present to produce the required effect? a) 2.5 kHz b) 5.005 kHz c) 5.5 kHz d) 10 kHz 5) A student attached a buzzer to a pendulum. She will hear the highest frequency when the buzzer is a) at the bottom moving toward her b) at the bottom heading away from her c) just before reaching the top d) just after reaching the top