Concepts Of Physics MCQ Edition [Volume 1]PhysicsWave Motion and Waves on a String
A particle on a stretched string supporting a travelling wave takes 5.0 ms to travel from its mean position to the extreme position. The distance separating two consecutive particles that are located at their mean positions is 2.0 cm . Determine the frequency, the wavelength, and the wave speed.
Options
- A100 Hz , 2.0 cm , 2.0 m s ⁻¹
- B50 Hz , 4.0 cm , 2.0 m s ⁻¹
- C25 Hz , 4.0 cm , 1.0 m s ⁻¹
- D50 Hz , 2.0 cm , 1.0 m s ⁻¹
Correct answer
B. 50 Hz , 4.0 cm , 2.0 m s ⁻¹
Step-by-step solution
The time taken by a particle to travel from its mean position to the extreme position is one-fourth of the time period T . T 4 = 5.0 ms T = 20.0 ms = 20 10⁻³ s The frequency f is given by: f = 1 T = 1 20 10⁻³ = 50 Hz The distance separating two consecutive particles that are simultaneously at their mean positions corresponds to half of the wavelength . 2 = 2.0 cm = 4.0 cm = 0.04 m The wave speed v is the product of frequency and wavelength: v = f = 50 0.04 = 2.0 m s ⁻¹