Q14.With what speed should a galaxy move outward with respect to earth so that the sodium- D line at wavelength ∘ ∘ 5890 A is observed at 5896 A? (1) 306 km sec−1 (2) 322 km sec−1 (3) 296 km sec−1 (4) 336 km sec−1
What This Question Tests
This question applies the Doppler effect for light to calculate the speed of a galaxy based on the observed redshift of a spectral line.
Concepts Tested
Formulas Used
Δλ/λ = v/c
📚 NCERT Sections This Tests
10.3 — (A) The Refractive Index Of Glass Is 1.5. What Is The Speed Of Light In
Physics Class 12 · Chapter 10
10.3 (a) The refractive index of glass is 1.5. What is the speed of light in glass? (Speed of light in vacuum is 3.0 × 108 m s–1) (b) Is the speed of light in glass independent of the colour of light? If not, which of the two colours red and violet travels slower in a glass prism?
10.1 — Monochromatic Light Of Wavelength 589 Nm Is Incident From Air On A
Physics Class 12 · Chapter 10
10.1 Monochromatic light of wavelength 589 nm is incident from air on a water surface. What are the wavelength, frequency and speed of (a) reflected, and (b) refracted light? Refractive index of water is 1.33.
11.6 — The Threshold Frequency For A Certain Metal Is 3.3 × 1014 Hz. If Light
Physics Class 12 · Chapter 11
11.6 The threshold frequency for a certain metal is 3.3 × 1014 Hz. If light of frequency 8.2 × 1014 Hz is incident on the metal, predict the cut- off voltage for the photoelectric emission.
📋 Question Details
- Chapter
- Wave Optics
- Topic
- Doppler effect in light
- Year
- 2021
- Shift
- 20 Jul Shift 2
- Q Number
- Q14
- Type
- MCQ
- NCERT Ref
- Class 12 Physics Ch 10: Wave Optics
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