A tuning fork of known frequency 256 ,Hz makes 5 beats per second… - Vidyadip

MCQ

A tuning fork of known frequency $256\,Hz$ makes $5$ beats per second with the vibrating string of a piano. The beat frequency decreases to $2$ beats per second when the tension in the piano string is slightly increased. The frequency of the piano string before increasing the tension was

A
$256 + 5 \,Hz$
B
$256 + 2\,Hz$
C
$256 -2 \,Hz$
✓
$256 -5\,Hz$

✓

Answer

Correct option: D.

$256 -5\,Hz$

d
(d) Suppose ${n_P} = $ frequency of piano $= ?$ $({n_P} \propto \sqrt T )$

${n_f} = $ Frequency of tuning fork $ = 256Hz$

$x =$ Beat frequency $= 5\, bps,$ which is decreasing $(5→2)$ after clanging the tension of piano wire Also, tension of piano wire is increasing so ${n_P} \uparrow $

Hence $n_P\uparrow-n_f = x\downarrow$ $\rightarrow$Wrong

$n_f -n_P\uparrow= x\downarrow$ $\rightarrow$Correct

$\Rightarrow$$n_P = n_f -x = 256 -5 \,Hz.$

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Explore more

JEE STD 11 Science question papers→Gujarat Board STD 11 Science question papers→Gujarat Board question paper generator→

Similar questions

Three fourth of the active decays in a radioactive sample in $3/4\, sec$. The half life of the sample is

Consider the following two statements $A$ and $B$ and identify the correct choice in the given answers

$A :$ Line spectra is due to atoms in gaseous state

$B :$ Band spectra is due to molecules

Two capillary tubes $ P$ and $Q$ are dipped in water. The height of water level in capillary $P$ is $2/3$ to the height in $Q$ capillary. The ratio of their diameters is

A uniform disc of radius $R$ is put over another uniform disc of radius $2R$ made of same material having same thickness.The peripheries of the two discs touches each other.Locate the centre of mass of the system taking center center of large disc at origin

An elastic spring under tension of $3 \mathrm{~N}$ has a lengtha. Its length is $b$ under tension $2 \mathrm{~N}$. For its length$(3 a-2 b)$, the value of tension will be_______. $\mathrm{N}$.

Three sound waves of equal amplitudes have frequencies $(n - 1 ), n, (n + 1 ).$ They superimpose to give beats. The number of beats produced per second will be

When heat in given to a gas in an isobaric process, then

In a vernier calliper, when both jaws touch each other, zero of the vernier scale shifts towards left and its $4^{\text {th }}$ division coincides exactly with a certain division on main scale. If $50$ vernier scale divisions equal to $49$ main scale divisions and zero error in the instrument is $0.04 \mathrm{~mm}$ then how many main scale divisions are there in $1 \mathrm{~cm}$ ?

The adjoining figure shows two different arrangements in which two square wire frames are placed in a uniform constantly decreasing magnetic field $B.$ The value of magnetic flux in each case is given by

An electron moving with a velocity ${\vec V_1} = 2\,\hat i\,\, m/s$ at a point in a magnetic field experiences a force ${\vec F_1} = - 2\hat j\,N$ . If the electron is moving with a velocity ${\vec V_2} = 2\,\hat j \,\,m/s$ at the same point, it experiences a force ${\vec F_2} = + 2\,\hat i\,N$ . The force the electron would experience if it were moving with a velocity ${\vec V_3} = 2\hat k$ $m/s$ at the same point is