Question 7 of 25 A sound wave with a wavelength of 26 m passes through glass, and then it
passes into air, where its wavelength changes to 1.6 m. If the sound wave has
a constant frequency of 220 Hz, what is its approximate speed as it passes
through the air? (The equation for the speed of a wave is v= f *1.)
O A. 3,500 m/s
B. 350 m/s
O C. 5,700 m/s
O D. 570 m/s

An automobile of mass 2000 kg moving at 30 m/s is braked suddenly with a constant braking force of 10000 n. how far does the car travel before stopping?

1. what is the relationship between wavelength and the penetrating power of an electromagnetic wave? a) the penetrating power has no relationship to the wavelength. b) the penetrating power increases as the wavelength increases. c) the penetrating power decreases as the wavelength increases. d) the penetrating power decreases as the wavelength decreases. 2. as ice melts and turns into water, the speed of sound through the material would most likely do what? justify your answer. a) the speed would not change because the material is always water. b) the speed of sound would increase because the density of water is less than that of ice. c) the speed of sound would increase because energy is added to ice in order to make it melt. d) the speed of sound would decrease because sound travels faster through solids than liquids. 3.which of these waves need a medium to travel through? a) sound b) x-rays c) infrared rays d) visible light

The drag force, fd, imposed by the surrounding air on a vehicle moving with velocity v is given by fd = cdaρv 2/2 where cd is a constant called the drag coefficient, a is the projected frontal area of the vehicle, and ρ is the air density. an automobile is moving at v = 80 kilometers per hour with cd = 0.28, a = 2.3 m2, and ρ = 1.2 kg/m3.