Chapter #1 Solutions - Introduction to Optics - Leno M Pedrotti, Leno S Pedrotti, Frank L Pedrotti - 3rd Edition

 

1. Calculate the de Broglie wavelength of (a) a golf ball of mass 50 g moving at 20 m/s and (b) an electron with kinetic energy of 10 eV. Get solution

2. The threshold of sensitivity of the human eye is about 100 photons per second. The eye is most sensitive at a wavelength of around 550 nm. For this wavelength, determine the threshold in watts of power. Get solution

3. What is the energy, in electron volts, of light photons at the ends of the visible spectrum, that is, at wavelengths of 380 and 770 nm? Get solution

4. Determine the wavelength and momentum of a photon whose energy equals the rest-mass energy of an electron. Get solution

5. Show that the rest-mass energy of an electron is 0.511 MeV. Get solution

6. Show that the relativistic momentum of an electron, accelerated through a potential difference of 1 million volts, can be conveniently expressed as 1.422 MeV/c, where c is the speed of light. Get solution

7. Show that the wavelength of a photon, measured in angstroms, can be found from its energy, measured in electron volts, by the convenient relation ... Get solution

8. Show that the relativistic kinetic energy, Ek = mc2(γ − 1)reduces to the classical expression ..., when υ≪ c. Get solution

10. Solar radiation is incident at the earth’s surface at an average of 1000 W/m2 on a surface normal to the rays. For a mean wavelength of 550 nm, calculate the number of photons falling on 1 cm2 of the surface each second. Get solution

11. Two parallel beams of electromagnetic radiation with different wavelengths deliver the same power to equivalent surface areas normal to the beams. Show that the numbers of photons striking the surfaces per second for the two beams are in the same ratio as their wavelengths. Get solution

13. What is the length of a half-wave dipole antenna designed to broadcast FM radio waves at 100 MHz? Get solution

14. A so-called “rabbit-ears” TV antenna is made of a pair of adjustable rods that can spread apart at different angles. If the rods are each adjusted to a quarter wavelength for a TV channel that has a middle frequency of 90 MHz, how long are the rods? Get solution

15. A soprano’s voice is sent by radio waves to a listener in a city 90 km away.a. How long does it take for the soprano’s voice to reach the listener?b. In the same time interval, how far from the soprano has the sound wave in the auditorium traveled? Take the speed of sound to be 340 m/s. Get solution

17. A 1.5-mW helium-neon laser beam delivers a spot of light 5 mm in diameter across a room 15 m wide. The beam radiates from a small circular area of diameter 0.5 mm at the output mirror of the laser. Assume that the beam irradiance is constant across the diverging beam.a. What is the beam divergence angle of this laser?b. Into what solid angle is the laser sending its beam?c. What is the irradiance at the spot on the wall 15 m from the laser?d. What is the radiance of the laser? Get solution