The horn on a motor scooter emit sound waves with a frequency of 440 Hz. The driver blows the horn as the scooter moves towards you at a speed of 12.5 m/s. What is the frequency of the sound you hear? Assume the temperature is 20°C.
Knowns Unknown

v = vd = fd = ?

vs = fs =

Solve for the Unknown  Use fd = fs[(v-vd)/(v-vs)] with vd = 0 m/s

Evaluate the Answer

Are the units correct?

Is the magnitude realistic?

The intensity of a polarized electromagnetic wave is 12 w/m^2. part a) what will be the intensity after passing through a polarizing filter whose axis makes the angle θ=0∘ with the plane of polarization? part b) what will be the intensity after passing through a polarizing filter whose axis makes the angle θ=30∘ with the plane of polarization? part c) what will be the intensity after passing through a polarizing filter whose axis makes the angle θ=45∘ with the plane of polarization? part d) what will be the intensity after passing through a polarizing filter whose axis makes the angle θ=60∘ with the plane of polarization? part e) what will be the intensity after passing through a polarizing filter whose axis makes the angle θ=90∘ with the plane of polarization?

Achlorine atom has 17 protons and 18 neutrons. what is its mass number? what is its atomic number?

Choose a realistic problem for which these are the correct freebody diagrams. be sure that the answer that the problem requests is consistent with the diagrams shown. choose a realistic problem for which these are the correct freebody diagrams. be sure that the answer that the problem requests is consistent with the diagrams shown. a 1.0 kg block is placed on top of a 2.0 kg block. a horizontal rope pulls the 2.0 kg block across a frictionless floor with a force of 21.0 n. the coefficient between the two blocks is 0.75. does the 1.0 kg block on top slide?