question archive 1) The beam of a green laser travels from air into Pyrex, then into water
1) The beam of a green laser travels from air into Pyrex, then into water
Subject:PhysicsPrice: Bought3
1) The beam of a green laser travels from air into Pyrex, then into water. Calculate the wavelength, in nanometres, of the green light in the Pyrex and in the water. The index of refraction for Pyrex is 1.47, the index of refraction for air is 1.0003, and the index of refraction for water is 1.33. The wavelength of the green laser is 5.30 x 10-7 m.
2. A ray of light travels from air into an optical fibre with an index of refraction of 1.44.
(a) In which direction does the light bend?
(b) The angle of incidence on the end of the fibre is 33 degree. Determine the angle of refraction inside the fibre.
3. A small light source shines upward from the bottom of a 35 cm-deep pond. When viewed from above, because of internal reflection, the light source makes a disc of light on the water's surface. Calculate the diameter of this disc.
4. A pattern of fringes appears on a screen 175 cm away, with a spacing of 7.7 mm between bright fringes. The wavelength of the light is 5.5 x 10-7 m. Determine the slit spacing.
5. Two cellphone towers separated by 550 m transmit an identical 790 MHz signal. You discover that you have an optimal signal while standing 12 km from each of the towers. The towers lie along a north-south line, and as you walk directly north, the signal decreases. Calculate how far north you must walk until you have an optimal signal again.
6. What angle is needed between the direction of polarized light and the axis of a polarizing filter to reduce its intensity by 90%?
7. (a) At what angle will light traveling in air be completely polarized horizontally when reflected from water (n=1.333)? (b) From glass (n=1.520)?
8. How does the energy of yellow light with a wavelength of 5.60 x 10^-7m compare to the energy of microwaves of frequency 15.0 GHz used in satellite imaging radar?
9. The AM radio station 680 News in Toronto uses a frequency of 680 kHz. Determine the corresponding wavelength.
10. You are shopping for sunglasses and want to test whether a pair you like has polarizing lenses or simply darkened plastic lenses. Describe two ways you could quickly test them.
