Q8 / 117 · NTA Abhyas (JEE Main) 2020 · Physics · Waves and Sound

In two similar wires of tension $16 N$ and $T$ , $3$ beats are heard, then $T =$

Correct answer
A
$49 N$
B
$25 N$
C
$64 N$
D
$80 N$

Solution

Here ,

T_{1} = 16 N, T_{2} = ?

As per the choice given,

T_{2} > T_{1}

∴ n_{2} > n_{1}, (n_{2} - n_{1}) = 3 \dots (i)

As

n \propto \sqrt{T}

∴ \frac{n_{2}}{n_{1}} = \sqrt{\frac{T}{16}} = \sqrt{\frac{T}{4}}

If

n_{1}

corresponds to

4 : n_{2}

corresponds to

3 + 4 = 7

, which is

\sqrt{T}

. Therefore,

T = 49 N

Hence, the correct answer is option: 'A'.

More Waves and Sound Questions

The displacement y of a particle in a medium can be expressed as y = 10 - 6 sin 100 t - 20x + π / 4 m , where t is in seconds and x in meter
A metallic rod of length 1 m , Young's modulus 3 × 10 11 N m - 2 and density 7 . 5 × 10 2 kg m - 3 is clamped at its middle. Longitudinal st
There is a source of sound (a tuning fork) moving towards a reflecting wall will a speed of 30 m s - 1 . The velocity of the sound in air is
The equation of a simple harmonic progressive wave is given by y = A sin ⁡ 100 π t - 3 x . Find the distance between 2 particles having a ph
A sound absorber attenuates the sound level by 20 dB. The intensity decreases by a factor of
A string fixed at both ends has a standing wave mode for which the distances between adjacent nodes is 18 cm. For the net consecutive standi