Q11.A wire of length L and mass per unit length 6.0 × 10−3 kg m−1 is put under tension of 540 N. Two consecutive frequencies that it resonates at are: 420 Hz and 490 Hz. Then L in meters is : (1) 2.1m (2) 1.1m (3) 8.1m (4) 5.1m
What This Question Tests
This question requires calculating the length of a string using the concept of consecutive resonance frequencies and the wave speed on a stretched string.
Concepts Tested
Formulas Used
f_n = n(v/2L)
v = √(T/μ)
📚 NCERT Sections This Tests
4.7 — Two Long And Parallel Straight Wires A And B Carrying Currents Of
Physics Class 11 · Chapter 4
4.7 Two long and parallel straight wires A and B carrying currents of 8.0 A and 5.0 A in the same direction are separated by a distance of 4.0 cm. Estimate the force on a 10 cm section of wire A.
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?
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.
📋 Question Details
- Chapter
- Waves & Sound
- Topic
- Standing waves in a stretched string
- Year
- 2020
- Shift
- 09 Jan Shift 2
- Q Number
- Q11
- Type
- MCQ
- NCERT Ref
- Class 11 Physics Ch 15: Waves
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