A factory siren indicating the end of a shift has a frequency of 80 Hz where the speed of sound in air is 343 m/s
What frequency is perceived by the occupant of a car that is traveling at 30 m/s (a) towards the factory and (b) away from the factory?
(a) 87 Hz (b) 73 Hz
You might also like to view...
For a plane to be able to fly clockwise in a horizontal circle as seen from above, in addition to exerting a force downwards on the air
a. it must be increasing its speed. b. it must exert a force on the air that is directed to the plane's left side. c. it must exert a force on the air that is directed to the plane's right side. d. it does not need to exert a force: it must only move the wing flaps out. e. it only needs to deflect the air without exerting any additional force on the air.
The existence of the Ring of Fire is best explained by the
a. theory of plate tectonics. b. principle of superposition. c. concept of uniformitarianism. d. law of catastrophism.
Which of the following best describes how the Drake equation is useful?
A) It tells us what wavelengths of light will be most useful to examine in the search for extraterrestrial intelligence. B) It allows us to calculate the masses of planets orbiting other stars. C) It has allowed us to determine the number of civilizations in the Milky Way Galaxy. D) It helps us understand what we need to know in order to determine the likelihood of finding other civilizations.
Determine the energy stored in the 40-?F capacitor
a.
2.4 mJ
b.
1.6 mJ
c.
2.0 mJ
d.
2.9 mJ
e.
4.0 mJ