Q30.A message signal of frequency 20 kHz and peak voltage of 20 V is used to modulate a carrier wave of frequency 1 MHz and peak voltage of 20 V. The modulation index will be:
What This Question Tests
This is a direct application of the formula for modulation index in amplitude modulation, calculating the ratio of peak voltages.
Concepts Tested
Formulas Used
μ = A_m / A_c
📚 NCERT Sections This Tests
4.10 — Two Moving Coil Meters, M1 And M2 Have The Following Particulars:
Physics Class 11 · Chapter 4
4.10 Two moving coil meters, M1 and M2 have the following particulars: R1 = 10 Ω, N1 = 30, A1 = 3.6 × 10–3 m2, B1 = 0.25 T R2 = 14 Ω, N2 = 42, A2 = 1.8 × 10–3 m2, B2 = 0.50 T (The spring constants are identical for the two meters). Determine the ratio of (a) current sensitivity and (b) voltage sensitivity of M2 and M1.
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.
10.5 — In Young’S Double-Slit Experiment Using Monochromatic Light Of
Physics Class 12 · Chapter 10
10.5 In Young’s double-slit experiment using monochromatic light of wavelength l, the intensity of light at a point on the screen where path difference is l, is K units. What is the intensity of light at a point where path difference is l/3?
📋 Question Details
- Chapter
- Communication Systems
- Topic
- Amplitude Modulation
- Year
- 2021
- Shift
- 25 Jul Shift 2
- Q Number
- Q30
- Type
- Numerical
- NCERT Ref
- Class 12 Physics Ch 15: Communication Systems
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