The wavelength of the sound wave of 15 hz, frequency is 0.0022 m. what is its speed?

For the car in the picture ,in which direction is the normal force? -into the screen -down -out of the screen -up

Light from two different sources are incident upon the same side of a polarizing filter. light from one source is polarized with total intensity ip, while light from the other source is unpolarized with total intensity iu. as you rotate the polarizing filter through 360 degrees, the intensity of the transmitted light on the other side varies by a factor of 9. what is the relative intensity of the initial polarized source to the unpolarized source, or ip/iu?

You notice the birds sitting on the electrical wires which of the following explain why the birds don't get shocked