Explain why the daytime sky looks blue

Assignment Help Physics
Reference no: EM1392646

Q. The process of scattering of light by a molecule (Rayleigh scattering) is an important physical phenomenon. Instead of thinking of scattering as light simply bouncing off the molecule, one should think of it as absorption followed by reradiation of light.

The probability for light to be scattered is proportional to the inverse of the wavelength to the fourth power, this means that the shorter wavelengths (toward blue) get scattered more strongly than the longer wavelengths (toward red).

Rayleigh scattering can explain why the daytime sky looks blue, the sunset looks red, and clouds are white. In the afternoon you observe mostly scattered light (blue); in evening you see mostly transmitted light (red). The clouds have higher concentration of water and ice droplets. This means that light gets rescattered many times and all wavelengths get a chance to scatter out of the clouds, adding up to white light.

Another effect that can be explained by light scattering is polarization. While you look at the sky with Polaroid sunglasses it appears darker or brighter from different angles. This is because the scattered light is partially polarized. The white light scattered from the clouds is unpolarized, since the light scatters randomly, multiple times. The direction of its polarization becomes random and thus the light is unpolarized. This effect can be useful for making dramatic photographs of the sky.

Consider a photographer who wants to take a picture of an interesting cloud formation. To increase the ratio of clouds' intensity to that of the blue sky the photographer uses a polarizing filter.

Find out the angle between the filter's polarizing axis and the direction of polarization of light necessary to increase the ratio of the clouds' intensity to that of blue sky so that it is three times the normal value.

Reference no: EM1392646

Questions Cloud

Apple to strengthen its position in significant market : What suggestions would you make to permit Apple to strengthen its position in its most significant markets? What steps must it take to make sure that iPad becomes a success.
Differentiate cellular signaling can occur : Discuss similarities and differences of the three ways cellular signaling can occur.
Explain offensive role or defensive role of company : What kind of strategy did each company use? Did they take the offensive role or defensive role? How did their strategy influence the outcome of their success?
Significant difference in proportions-level of significance : Assuming 250 of each sex, can we conclude that there is a significant difference in the proportions at a 0.05 level of significance?
Explain why the daytime sky looks blue : Find out the angle between the filter's polarizing axis and the direction of polarization of light necessary to increase the ratio of the clouds' intensity to that of blue sky so that it is three times the normal value.
Probability of random letter selection : Many newspapers carry a certain puzzle in which the individual must unscramble letters to form words. How many ways can the letters of YARNLE be arranged?
Find out the utmost stress : The femur is a bone in the leg whose minimum cross-sectional area is about 4.5 x 10-4 m2. A compression force in excess of 7.7 x 104 N will fracture this bone. Bone has a compression Young's modulus of 9.4 x 10^9 N/m2
Mean waiting times in the four locations : At the 0.05 level of significance, is there evidence of a difference in the mean waiting times in the four locations? State your null and alternative hypotheses. (Note: while the small sample size could justify use of the non- parametric Kruskal-W..
Find out the speed of the car at the bottom : A 2.10 x 10^3 kg car starts from rest at the top of a 4.70 m long driveway that is inclined at 25° with the horizontal. If an average friction force of 4.0 x10^3 N impedes motion, find out the speed of the car at the bottom of the driveway.

Reviews

Write a Review

Physics Questions & Answers

  Find force of friction

A 6 kg block, starting from rest, slides down a frictionless incline of length 2 m. When it arrives at the bottom of the incline its speed is vf. At what distance from the top of the incline is the speed of the block 0.5 vf.

  What is the velocity of the suspended mass

A single slit has a width of 2.1x10^(-6)m and is used to form the diffraction pattern. Find out the angle that locates the second second dark fringe when the wavelength of the light is 430 nm.

  What is the magnitude of the average induced emf

The coil is flipped so its plane is vertical to the magnetic field in 0.050 s. What is the magnitude of the average induced emf.

  How fast is the boy sliding

The mass of a space shuttle is approximately 2.0x10^6 kg. Throughout lift-off, the net force on the shuttle is 1.0x10^7 newtons directed upward. What is the speed of the shuttle 10 seconds after liftoff.

  What was the speed of the cannon ball

Old naval ships fired 10kg cannon balls from a 250 kg cannon. It was very important to stop the recoil of the cannon, as otherwise the heavy cannon would go careening across the deck of the ship.

  Find out the electric field at a point

A 220 g block is attached to a horizontal spring and executes simple harmonic motion with a period of 0.150 s. If the total energy of the system is 3.50 J.

  What is the earths velocity after the collision

Eight identical, non-interacting particles are placed in a cubical box of sides L = 0.2 nm. Find the lowest energy of the system (in electron volts) and list the quantum numbers of all occupied states if (a) particles are electrons and (b) particles..

  What is the terminal speed at the paratrooper

If the perceived frequency becomes constant at 440 Hz, what is terminal speed at the paratrooper? Take the speed sound in air to be 343 m/s and assume the paratrooper always remains below the helicopter.

  Where would the golf ball fall back to the ground

For a science fair competition, a group of high school students build a kicker-machine that can launch a golf ball from the origin with a velocity of 37.5 m/s and initial angle of 38.4° with respect to the horizontal.

  Compute the magnitude & direction of the current

Compute the magnitude & direction of the current.

  Calculate the work the crane performs

A certain type of laser emits light that has a frequency of 5.6 x 10^14 Hz. The light, however, occurs as a series of short pulses, each lasting for a time of 3.9 x 10-11 s.

  How many electrons are transferred to the screen

The center of a 1.40km diameter spherical pocket of oil is 1.5 km beneath the Earth's surface.Estimate by what percentage directly above the pocket of oil would differ from expected value of g for a uniform Earth? Assume the density of oil is 8.0 ..

Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd