Which of the following is NOT true for electromagnetic waves? (a) they transport

Question

Which of the following is NOT true for electromagnetic waves? (a) they transport energy (b) they transport momentum (c) they consist of changing electric and magnetic fields (d) they travel at different speeds vacuum, depending on their frequency (e) they can be reflected We perceive frequency for sound wave as pitch. What do we perceive frequency for light waves? (a) color (b) Brightness (c) Opacity (d) Shininess Unpolarized light passes through a single polarizer with an intensity of 10.00 mW/m^3. What is the intensity of the light upon exiting the polarizer? (a) 2.50 mW/m^2 (b) 5.00 mW/m^2 (c) 7.50 mW/m^3 (d) 10.00 mW/m^2 Which property of a light wave does not change as the wave passes from one transparent medium to another: (a) Frequency (b) Wavelength (c) Phase velocity (d) Amplitude Considering what you would observe on a nice day, which color of light do you think scatters moat in the atmosphere? (a) Blue (b) Red (c) Yellow (d) White (all colors scatter the same) The physical phenomenon that makes fiber optic signal transmission possible is (a) Dispersion (b) Polarization by reflection (c) Small angle refraction (d) Total internal reflection

Explanation / Answer

5. Electromagnetic waves can usually travel in vacuum . all the waves lying in electromagnetic spectrum travel at speed of light which is 3*108.

6. The frequency is no. of waves passing through a point in space in 1 sec. For light waves, it is percieved as color which ranges from 430 trillion hertz to 740 trillion hertz.

7. When light passes through a polarizer, we have two components for amplitude 1. passing light 2. Blocked light. In case of unpolarized light, both these amplitudes are equal. Intensity is proportional to square of amplitude.

we have, passed light intesnity = light intensity/2

8. When light passes from onr medium to other medium, the energy contained in the wave never changes. we know that E = hc/lambda and c/lamba = frequency. It implies that as energy doesnt change, frequency is also unchanged.

9. The phenomena of scattering takes place when sunlight enters our atmosphere. Due to presence of oxygen and nitrogen is air, these scattering will result. The white light splits into 7 colors (VIBGYOR) or (ROYGBIV). BIV have higher frequencies and become scattered while ROYG with low frequency passes throught the atmosphere. Actually, violet light is more easily scattered but our eyes are more sensitive to blue light, thats the reason on a good, fine day, we see the sky as blue.

10. An optic fibre cable usually has two parts 1. cladding 2. core. Core is more denser than cladding. when a light ray enters the optical fibre, it reflects off the surface at critical angle and this process continues inside the core of fibre.

Related Questions

Navigate

• Browse (All)
• Browse W
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.