Waves · Physics · TS EAMCET
MCQ (Single Correct Answer)
1
The tension applied to a metal wire of one metre length produces an elastic strain of $1 \%$. The density of the metal is $8000 \mathrm{kgm}^{-3}$ and Young's modulus of the metal is $2 \times 10^{11} \mathrm{Nm}^{-2}$. The fundamental frequency of the transverse waves in the metal wire is
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2
Two closed pipes when sounded simultaneously in their fundamental modes produce 6 beats per second. If the length of the shorter pipe is 150 cm , then the length of the longer pipe is
(Speed of sound in air $=336 \mathrm{~ms}^{-1}$ )
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3
The path difference between two particles of a sound wave is 50 cm and the phase difference between them is $1.8 \pi$. If the speed of sound in air is $340 \mathrm{~ms}^{-1}$, the frequency of the sound wave is
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4
A source at rest emits sound waves of frequency 102 Hz . Two observers are moving away from the source of sound in opposite directions each with a speed of $10 \%$ of the speed of sound. The ratio of the frequencies of sound heard by the observes is
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5
The difference between the fundamental frequencies of an open pipe and a closed pipe of same length is 100 Hz . The difference between the frequencies of the second harmonic of the open pipe and the third harmonic of the closed pipe is
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6
The displacement equations of sound waves produced by two sources are given by $y_1=5 \sin 400 \pi t$ and $y_2=8 \sin 408 \pi t$, where $t$ is time in seconds. If the waves are produced simultaneously, the number of beats produced per minute is
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7
A boy standing on a platform observes the frequency of a train horn as it passes by. The change in the frequency noticed as the train approaches and recedes him with a velocity of 108 kmph is (speed of sound in air $=330 \mathrm{~ms}^{-1}$ )
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8
If three sources of sound of frequencies $(n-1), n$ and $(n+1)$ are vibrated together, the number of beats produced and heard per second respectively are
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9
A car travelling at a speed of 54 kmph towards a wall sounds horn of frequency 400 Hz . The difference in the frequencies of two sounds, one received directly from the car and other reflected from the wall noticed by a person standing between the car and the wall is (speed of sound in air is $335 \mathrm{~m} / \mathrm{s}$ )
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10
The speed of a transverse wave in a stretched string $A$ is $v$. Another string $B$ of same length and same radius is subjected to same tension. If the density of the material of the string $B$ is $2 \%$ more than that of $A$ then the speed of the transverse wave in string $B$ is
TG EAPCET 2024 (Online) 9th May Morning Shift