While walking on the Moon, you cannot hear the sound of stones cracking behind you because:
| 1. | Sound waves need a medium to travel through. |
| 2. | Sound waves are transverse. |
| 3. | The acceleration due to gravity on the Moon is very small. |
| 4. | Sound waves are longitudinal. |
A wave travelling in the positive x-direction having maximum displacement along y-direction as 1m, wavelength 2π m and frequency of 1/π Hz is represented by
1. y=sin(x-2t)
2. y=sin(2πx-2πt)
3. y=sin(10πx-20πt)
4. y=sin(2πx+2πt)
A transverse wave is represented by y= For what value of the wavelength is the wave velocity equal to the maximum particle velocity?
(1)
(2)
(3)
(4) A
A transverse wave is described by the equation . The maximum particle velocity is four times the wave velocity if :
(1)
(2)
(3)
(4)
| Column-I | Column-II | Column-III | |||||
| (A) | \(\small0.04\sin(10x+600t) \) | (P) | sinusoidal waveform | (I) | speed \(=30~\text{m/s}\) | ||
| (B) | \(\small0.008\sin^2(10x-300t)\) | (Q) | wave pulse | (II) | speed \(=60~\text{m/s}\) | ||
| (C) | \(\small\dfrac{3\times10^{-3}}{(10x+600t)^2+400}\) | (R) | combination of waveforms | (III) | moving along positive \(x\) | ||
| (D) | \(\small(2\times10^{-3})\sin10x \cdot\cos300t\) | (IV) | moving along negative \(x\) | ||||
| (V) | moving in the opposite direction | ||||||
| 1. | A-P,II,III; B-Q,I,IV; C-Q,II,III; D-R,I |
| 2. | A-P,II,IV; B-P,I,III; C-Q,II,IV; D-R,I,V |
| 3. | A-P,I,III; B-Q,I,IV; C-R,III; D-R,I,IV |
| 4. | A-P,I,III; B-Q,I,III; C- R-II,IV; D-R,I,V |
| Assertion (A): | When a beetle moves along the sand within a few tens of centimetres of a sand scorpion, the scorpion immediately turns towards the beetle and dashes towards it. |
| Reason (R): | When a beetle disturbs the sand, it sends pulses along the sand's surface. One set of pulses is longitudinal while the other set is transverse. |
| 1. | Both (A) and (R) are True and (R) is the correct explanation of (A). |
| 2. | Both (A) and (R) are True but (R) is not the correct explanation of (A). |
| 3. | (A) is True but (R) is False. |
| 4. | Both (A) and (R) are False. |
| 1. | its frequency changes |
| 2. | its wavelength changes |
| 3. | both frequency and wavelength change |
| 4. | both frequency and wavelength remain unchanged |
Which of the following is not possible for sound waves in air?
1. beats
2. interference
3. diffraction
4. polarization
| 1. | \(3~\text {m/s}\) | 2. | \(4~\text {m/s}\) |
| 3. | \(12~\text {m/s}\) | 4. | \(48~ \text {m/s}\) |
A transverse wave with an amplitude of \(0.5\) m, a wavelength of \(1\) m, and a frequency of \(2\) Hz is propagating along a string in the negative \(x\)-direction. The expression for this wave is:
1. \(y(x,t)=0.5~ \text{sin}(2 \pi x-4\pi t)\)
2. \(y(x,t)=0.5~ \text{cos}(2 \pi x+4\pi t)\)
3. \(y(x,t)=0.5~ \text{sin}( \pi x-2\pi t)\)
4. \(y(x,t)=0.5~ \text{cos}(2 \pi x+2\pi t)\)