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4 years ago

13

A penny falls from a windowsill which is 25.0 m above the sidewalk. How much time does a passerby on the sidewalk below have to

move out of the way before the penny hits the ground?

1 answer:

Yanka [14]4 years ago

4 0

You need to know the formula:

25 = 1/2 * g * t^2

t = √(50/g) = 2.258 s, where I use g = 9.8 m/s^2

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where

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From the equation, we see that the electric field and the magnetic field are directly proportional: therefore, if the rms value of the electric field is doubled, then the rms value of the magnetic field will double as well.

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The intensity of an electromagnetic wave is given by

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