Speed of Travelling Wave NEET Questions

Physics - Oscillations and Waves

Speed of Travelling Wave MCQ Questions


7.
The speed of transverse waves on a string: v = √(T/μ). If both the tension T and linear mass density μ are doubled simultaneously, the wave speed:
A.
Remains unchanged: v' = √(2T/2μ) = √(T/μ) = v
B.
Doubles: v' = 2v
C.
Increases by √2: v' = √2 · v
D.
Halves: v' = v/2
😑 View Answer Rough Work Error
ANSWER :
A. Remains unchanged: v' = √(2T/2μ) = √(T/μ) = v
8.
A string of length L is stretched between two fixed supports. If tension T is maintained and the string's mass is doubled (to 2m) while its length remains L, the new wave speed is:
A.
v' = v/2 (halved)
B.
v' = v/√2 (slower), since μ' = 2m/L = 2μ, giving v' = √(T/2μ) = v/√2
C.
v' = √2 · v (faster)
D.
v' = 2v (doubled)
😑 View Answer Rough Work Error
ANSWER :
B. v' = v/√2 (slower), since μ' = 2m/L = 2μ, giving v' = √(T/2μ) = v/√2
9.
The wave speed on a string is v = √(T/μ). The speed does NOT depend on which of the following?
A.
Both T and μ
B.
The tension T in the string
C.
The linear mass density μ of the string
D.
The frequency ν and amplitude a of the wave (v depends only on T and μ, properties of the medium)
😑 View Answer Rough Work Error
ANSWER :
D. The frequency ν and amplitude a of the wave (v depends only on T and μ, properties of the medium)
10.
A transverse wave travels along a string at speed v. The string is now replaced by one made of denser material such that its linear mass density is 4μ, with the same tension T. A new wave at the same frequency ν is sent along this denser string. Which statement is correct?
A.
New wave speed v' = v/2; new wavelength λ' = 2λ
B.
New wave speed v' = v/2; new wavelength λ' = λ/2; frequency remains ν (frequency is set by source, not medium)
C.
New wave speed v' = v/2; new wavelength λ' = λ; frequency changes to ν/2
D.
New wave speed v' = 2v; new wavelength λ' = 2λ
😑 View Answer Rough Work Error
ANSWER :
B. New wave speed v' = v/2; new wavelength λ' = λ/2; frequency remains ν (frequency is set by source, not medium)
11.
For the transverse wave y(x,t) = 0.005 sin(80x − 3t) m, what are the wave speed, wavelength, and time period?
A.
v = 80/3 ≈ 26.7 m/s; λ = 80 m; T = 3 s
B.
v = 0.0375 m/s; λ = 2π/80 ≈ 0.0785 m = 7.85 cm; T = 2π/3 ≈ 2.09 s
C.
v = 3 × 80 = 240 m/s; λ = 3 m; T = 80 s
D.
v = 3 m/s; λ = 0.005 m; T = 80 s
😑 View Answer Rough Work Error
ANSWER :
B. v = 0.0375 m/s; λ = 2π/80 ≈ 0.0785 m = 7.85 cm; T = 2π/3 ≈ 2.09 s
12.
A steel wire of length 0.72 m and mass 5.0 × 10⁻³ kg is under tension 60 N. The speed of transverse waves on this wire is:
A.
Approximately 93 m/s, using v = √(T/μ) with μ = m/L = 6.94 × 10⁻³ kg/m
B.
Approximately 9.3 m/s
C.
Approximately 0.93 m/s
D.
Approximately 930 m/s
😑 View Answer Rough Work Error
ANSWER :
A. Approximately 93 m/s, using v = √(T/μ) with μ = m/L = 6.94 × 10⁻³ kg/m