To solve this problem we will apply the concepts related to the Doppler effect. The Doppler effect is the change in the perceived frequency of any wave movement when the emitter, or focus of waves, and the receiver, or observer, move relative to each other. Mathematically it can be described as,
Here,
= Frequency of Source
= Speed of sound
f = Frequency heard before slowing down
f' = Frequency heard after slowing down
v = Speed of the train before slowing down
So if the speed of the train after slowing down will be v/2, we can do a system equation of 2x2 at the two moments, then,
The first equation is,
Now the second expression will be,
Dividing the two expression we have,
Solving for v, we have,
Therefore the speed of the train before and after slowing down is 22.12m/s
Given that the density of heptane is
The mass of heptane is
The density of water is
The mass of water is
The volume of heptane will be
The volume of water will be
Thus, the volume of heptane is 45.32 mL and the volume of water is 37 mL.
The total volume of liquid in the cylinder will be
The total volume of liquid in the cylinder will be 82.32 mL.
The molecules are continually colliding with each other and with the walls of the container. When a molecule collides with the wall, they exert<span> small force on the wall The </span>pressure exerted<span> by the </span>gas<span> is due to the sum of all these collision forces.The more particles that hit the walls, the higher the </span>pressure<span>.</span>