During a thunderstorm, the thunder in the sky is produced by the_____.

$1$. Meeting of cumulonimbus clouds in the sky.

$2$. Lightning that separates the nimbus clouds.

$3$. Violent upward movement of air and water particles.

Select the correct answer using the codes given below.

Consider the following statements:

$1$. A widely used musical scale called the diatonic scale has seven scales.

$2$. The frequency of the note Sa (Sa) is $256$ Hz and that of Ni $512$ Hz.

Which of the statements given above is/are correct?

Assertion (A): A jet aircraft moving at Mach number equal to 1 travel faster at an altitude of 15 km than while moving at Mach number equal to 1 near the sea level.

Reason (R): The velocity of sound depends on the temperature of the surrounding medium.

Consider the following statements:

1. A flute of smaller length produces waves of lower frequency

2. Sound travels in rocks in the form of longitudinal elastic waves only

Which of the statements given above is/are correct?

What does the term Dolby B or Dolby C printed on tape-recorders and other sound systems refer to?

Consider the following statements:

Statement I: The velocity of sound in air increases due to the presence of moisture in it.

Statement II: The presence of moisture in the air lowers the density of air.

Which of the above statement (s) is/are correct?

Consider the following statements:

Statement I: When a particle is executing simple harmonic motion, total energy varies with time.

Statement II: Audible waves have a frequency range of $30$ kHz to $30$ MHz.

Which of the above statement (s) is/are correct?