This question has Statement 1 and Statement 2 .Of the four choice… - Vidyadip

Question

This question has Statement $1$ and Statement $2$ .Of the four choices given after the Statements, choose the one that best describes the two Statements.
Statement $1$ : Bats emitting ultrasonic waves can detect the location of a prey by hearing the waves reflected from it.
Statement $2$ : When the source and the detector are moving, the frequency of reflected waves is changed

✓

Answer

Bats catch the prey by hearing reflected ultrasonic waves. When the source and the detector (observer) are moving, frequency of reflected waves change . This is according to Doppler's effect

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

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

Similar questions

When a biconvex lens of glass having refractive index $1.47$ is dipped in a liquid, it acts as a plane sheet of glass. This implies that the liquid must have refractive index

The thermal conductivity of a material in $CGS$ system is $0.4$ . In steady state, the rate of flow of heat $10 cal/sec-cm2$ , then the thermal gradient will be ....... $^oC/cm$

Three immiscible liquids of densities $d_1 > d_2 > d_3$ and refractive indices ${\mu _1} > {\mu _2} > {\mu _3}$ are put in a beaker. The height of each liquid column is $\frac{h}{3}$. A dot is made at the bottom of the beaker. For near normal vision, find apparent depth of the dot

The electric current in a circular coil of $2$ turns produces a magnetic induction $B _{1}$ at its centre. The coil is unwound and is rewound into a circular coil of $5$ turns and the same current produces a magnetic induction $B _{2}$ at its centre.The ratio of $\frac{ B _{2}}{ B _{1}}$ is.

Consider the following statements:

$I$. All isotopes of an element have the same number of neutrons.

$II$. Only one isotope of an element can be stable and non-radioactive.

$III$. All elements have isotopes.

$IV$. All isotopes of carbon can form chemical compounds with oxygen-$16$.

Choose the correct option regarding an isotope.

A stone is dropped from the top of a building. When it crosses a point $5\, m$ below the top, another stone starts to fall from a point $25\, m$ below the top. Both stones reach the bottom of building simultaneously. The height of the building is ..... $m$.

The internal resistance of a primary cell is $4\, ohm$. It generates a current of $0.2\, amp$ in an external resistance of $21\, ohm$. The rate at which chemical energy is consumed in providing the current is .............. $J/s$

Given below are two statements: one is labelled as Assertion $A$ and the other is labelled as Reason $R$.

Assertion $A$: The potential ( $V$ ) at any axial point, at $2 \mathrm{~m}$ distance ( $r$ ) from the centre of the dipole of dipole moment vector $\vec{P}$ of magnitude, $4 \times 10^{-6} \mathrm{C} \mathrm{m}$, is $\pm 9 \times 10^3 \mathrm{~V}$.

(Take $\frac{1}{4 \pi \epsilon_0}=9 \times 10^9 \mathrm{Sl}$ units)

Reason $R$: $V= \pm \frac{2 P}{4 \pi \epsilon_0 r^2}$, where $r$ is the distance of any axial point, situated at $2 \mathrm{~m}$ from the centre of the dipole.

In the light of the above statements, choose the correct answer from the options given below:

The ratio of wavelength of spectral lines $H_\alpha$ and $H _\beta$ in the Balmer series is $\frac{x}{20}$. The value of $x$ is $...............$

Velocity of sound in air is