Speed of a Travelling Wave

IMPORTANT

Speed of a Travelling Wave: Overview

This topic covers concepts such as Wave Speed, Wave Velocity in Wires, Speed of Sound Waves, Newton's Formula for Speed of Sound Waves in Gases, Laplace Correction of Newton's Relation, Pressure and Speed of Sound Wave, etc.

Important Questions on Speed of a Travelling Wave

MEDIUM
IMPORTANT

The equation of a wave on a string of linear mass density 0.04 kg m-1 is given by,  y=0.02msin2πt0.04(s)-x0.50(m).

The tension in the string is n×10-2 N. Write the value of n.

MEDIUM
IMPORTANT

Speed of a transverse wave in a string depends on the tension and linear mass density of the string. Find the formula for the speed of the wave in the string.

EASY
IMPORTANT

Speed of a longitudinal wave in a medium is given by, v=Ed, where E is elasticity of the medium and d is its density. 

EASY
IMPORTANT

Compare the velocities of the waveforms given below, and choose the correct option.

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where,vA, vB, vC andvD are velocities given in (A), (B), (C) and (D), respectively.

EASY
IMPORTANT

To increase the frequency from 100 Hz to 400 Hz, the tension in the string has to be changed by,

EASY
IMPORTANT

The rope shown at an instant is carrying a wave travelling towards right, created by a source vibrating at a frequency n.

Consider the following statements:
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MEDIUM
IMPORTANT

Two Cu wires of radii R1 and R2, such that R1>R2. Then, which of the following is true? 

MEDIUM
IMPORTANT

A sonometer wire 1 metre along weighing 2 g is in resonance with a tuning fork of frequency 300 Hz. Magnitude of tension in Newton in the sonometer wire is 

HARD
IMPORTANT

A solid ball is suspended from the ceiling of a motor car through a light string. A transverse pulse travels at the speed 60 cm s-1 on the string when the car is at rest. When the car accelerates on a horizontal road, speed of the pulse is 66 cm s-1. The acceleration of the car is nearly g=10 ms-2

MEDIUM
IMPORTANT

A uniform rope of length 12 m and mass 6 kg hangs vertically from a rigid support. A block of mass 2 kg is attached to the free end of the rope. A transverse pulse of wavelength 0.06 m is produced at the lower end of the rope. Wavelength of the pulse when it reaches the top of the rope is ______.

EASY
IMPORTANT

The frequency of tuning fork is 500 Hz and the velocity of sound in air is 300 m s-1. The distance travelled by sound while the fork executes 100 oscillations per second is ______.

EASY
IMPORTANT

The ratio of the speed of sound in nitrogen gas to that in helium gas at 300 K is

EASY
IMPORTANT

What is the ratio of velocities of sound waves in oxygen and hydrogen if their density are in ratio 16:1?

EASY
IMPORTANT

What will be the speed of the transverse wave in a 2.5 m long rope hanging from the ceiling at the upper end and at a point 0.5 m distance from the lower end respectively? Given the mass of the rope is 0.1 Kg distributed uniformly.

EASY
IMPORTANT

Two steel wires A and B are such that the diameter of A is twice that of B and the tension in A is half of that in B. If transverse waves of same frequency are generated in both the wires, then compute the ratio of velocities of waves in A and B.

EASY
IMPORTANT

A wave given by the equation y = 0.021 sin (x + 30t), where, x and y are measured in metre and t in second is propagating in a string with linear density 1.3×10-4 Kg m-1.  Calculate the tension in the string.

MEDIUM
IMPORTANT

Considering the compositions of air to be 76% Nitrogen and 26% Oxygen by weight, calculate the velocity of sound in air. (Molecular weights of Nitrogen and Oxygen are 28 and 32, respectively, and γ=1.4.)

EASY
IMPORTANT

The respective displacements (in cm) of two particles of a medium, disturbed by the wave propagation at x1=0 and x2=1 cm can be given by the equations,

y1=2sin3πt
y2=2sin3πt-π8

What is the wave speed?

HARD
IMPORTANT

Find the wave velocity for 20x.

MEDIUM
IMPORTANT

A man standing between two parallel hills, claps his hand and hears successive echoes at regular intervals of 1 s. If velocity of sound is 340 m s-1, then the distance between the hills is