Physics, 01.08.2019 23:00 googoo4

Asoap bubble is essentially a thin film of water surrounded by air. the colors you see in soap bubbles are produced by interference. part a what visible wavelengths of light are strongly reflected from a 390-nm-thick soap bubble?

Answers: 1

Show answers

Answers

Answer from: tadeebun

The colors we see in the bubble are produced by the interference between two waves: a) the wave reflected by the surface of the bubble b) the wave that travels inside the bubble and it is reflected by its back.
The condition for the constructive interference is that the phase shift between the two waves is an integer multiple of $2\pi$ . The phase difference between the two waves is
$\Delta \phi = k \Delta x - \pi$
where $\Delta x = 2t$ is twice the thickness of the bubble (since the second wave travels inside the bubble and it is reflected from the back), while $\pi$ is due to the fact that the first wave has an extra phase shift $\pi$ because it is reflected from a material (soap) with higher refraction index than the air.

So, in order to have constructive interference, we should require
$k \Delta x - \pi = 2m\pi$
where m is an integer. Substituting $\Delta x=2t$ and $k= \frac{2 \pi}{\lambda}$ , we have
$\lambda = \frac{2t}{m+ \frac{1}{2} }$
But here $\lambda$ is the wavelength in the soap; we need instead the wavelength in the air, which is
$\lambda' = n \lambda$
where n=1.33 is the refraction index.

Therefore, we have
$\lambda' = \frac{2nt}{m+ \frac{1}{2} }$

Using t=390 nm, and using different values of m, we find tha only m=1 and m=2 have wavelength in the visible spectrum: $\lambda'=415 nm$ and $\lambda'=692nm$ . These wavelengths correspond to red and violet, so the bubble appears as red-violet.

Answer from: Quest

Is a vector quantity that refers to "the rate at which an object changes its position." imagine a person moving rapidly - one step forward and one step back - always returning to the original starting position. while this might result in a frenzy of activity, it would result in a zero velocity. because the person always returns to the original position, the motion would never result in a change in position. since velocity is defined as the rate at which the position changes, this motion results in zero velocity. if a person in motion wishes to maximize their velocity, then that person must make every effort to maximize the amount that they are displaced from their original position. every step must go into moving that person further from where he or she started. for certain, the person should never change directions and begin to return to the starting position.

Answer from: Quest

Bag of bolts weight 29.4n

Another question on Physics

Physics, 21.06.2019 23:30

Which simple machine is not part of this compound machine? a. lever b. pulley c. inclined plane d. wheel and axle

Answers: 1

Answer

Physics, 22.06.2019 10:00

Because air contracts as it cools, the air pressure inside a freezer is typically lower than on the outside. why do ice cubes inside a freezer tend to shrink over time? a. the ice dissolves oxygen from the air, forming a denser crystalline matrix.b. the ice reacts chemically with carbon dioxide in the air, forming gaseous carbon compounds.c. the ice melts, and then the liquid freezes as ice crystals on the bottom of the freezer.d. the ice sublimes, and then the water vapor deposits as ice crystals on the sides of the freezer.

Answers: 1

Answer

Physics, 22.06.2019 11:30

Which of the following is the phase that results when the moon is on the opposite side of the earth from the sun? a. quarter moon b. crescent moon c. new moon d. full moon

Answers: 1

Answer

Physics, 22.06.2019 11:50

Select all that applywhat are some basic resources a family is expected to provide for children? educationclothesspending

Answers: 2

Answer

You know the right answer?

Asoap bubble is essentially a thin film of water surrounded by air. the colors you see in soap bubbl...

Questions