Question

What is the speed of sound at the atmospheric temperature of 30°C?

Answer 1

Answer:

Option C is the correct answer.

Explanation:

The speed of sound in air is given approximately by  

$v=331.4+0.6T_c$

Here $T_c$ is the temperature in degree Celsius.

Temperature $T_c=30^0C$

Substituting we will get

     v = 331.4 + 0.6 x 30 = 349.4 m/s

Option C is the correct answer.

Answer 2

The parcel will undergo projectile motion, which means that it will have motion in both the horizontal and vertical direction.

First, we determine how long the parcel will fall using:

s = ut + 1/2 at²

where s will be the height, u is the initial vertical velocity of the parcel (0), t is the time of fall and a is the acceleration due to gravity.

5.5 = (0)(t) + 1/2 (9.81)(t)²

t = 1.06 seconds

A