Which of the following scenarios would produce the Doppler Effect? Check all that apply.

A moving sound source (such as an airplane passing overhead)

A moving observer of a source (such as a person running past a loud
stereo)

A moving source and moving observer (such as kids chasing an ice
cream truck that is playing music)

A non-moving source and non-moving observer (such as person
watching television on a couch)

1. a net force of 100 newton’s is applied to a wagon for 5 seconds. this causes the wagon to undergo a change in momentum of

A3.9 g aluminum foil ball with a charge of +4.1×10−9 c is suspended on a string in a uniform horizontal e⃗ field. the string deviates to the right and makes an angle of 30∘ with the vertical. part a part complete what information about the e⃗ field can you determine for this situation? what information about the field can you determine for this situation? only the magnitude of e⃗ only the direction of e⃗ both the magnitude and the direction of e⃗ none of the above previous answers correct part b determine the magnitude of the electric field. express your answer with the appropriate units. e e = nothing nothing request answer part c determine the direction of the electric field. determine the direction of the electric field. to the right to the left away from you toward you

How do we measure or think of speed in the united states?