NEET Waves — Set 8

Question 1

A transverse wave on a string has a tension of 200 N and a linear mass density of 0.04 kg/m. What is the wavelength if the frequency is 25 Hz?

Accepted Answer

Speed: $ v = \sqrt{\frac{T}{\mu}} = \sqrt{\frac{200}{0.04}} = \sqrt{5000} \approx 70.71 \, \text{m/s} $. Wavelength: $ \lambda = \frac{v}{v} = \frac{70.71}{25} \approx 2.83 \, \text{m} $.

Question 2

Which characteristic of a wave remains constant when it travels from one medium to another with different properties?

Accepted Answer

When a wave crosses a boundary between media, its speed and wavelength change due to differing medium properties, but frequency remains constant as it is determined by the source.

Question 3

A pipe closed at one end has a length of 0.4 m and a speed of sound of 320 m/s. What is its fundamental frequency?

Accepted Answer

For closed pipe: $ v_1 = \frac{v}{4L} $. $ v_1 = \frac{320}{4 \times 0.4} = \frac{320}{1.6} = 200 \, \text{Hz} $.

NEET Physics: Waves — Practice Set 8

Q1. A transverse wave on a string has a tension of 200 N and a linear mass density of 0.04 kg/m. What is the wavelength if the frequency is 25 Hz?

Q2. Which characteristic of a wave remains constant when it travels from one medium to another with different properties?

Q3. A pipe closed at one end has a length of 0.4 m and a speed of sound of 320 m/s. What is its fundamental frequency?

Q4. What is the phase change when a longitudinal wave reflects off a rigid boundary?

Q5. A string fixed at both ends vibrates in its second harmonic with a frequency of 80 Hz. If its length is 1 m, what is the wave speed?

Q6. A stationary wave on a string fixed at both ends has a wavelength of 0.4 m and a frequency of 150 Hz. What is the wave speed?

Q7. A stationary wave on a string fixed at both ends has a frequency of 80 Hz and a wave speed of 32 m/s. What is the length of the string?

Q8. A transverse wave on a string has a tension of 90 N and a linear mass density of 0.01 kg/m. What is the frequency if the wavelength is 1.5 m?

Q9. A wave is described by \( y(x, t) = 0.01 \sin (40x - 80t) \), where \( x \) and \( y \) are in meters and \( t \) in seconds. What is the frequency of the wave?

Q10. What is the primary physical quantity that remains constant for a wave reflecting off a boundary within the same medium?