Answer:

Explanation:
Given:
- original frequency of sound wave,

- speed of the sound source,

- original speed of sound wave from the source,

<u>According to the Doppler's effect:</u>

The sound is reflected from the wall and the source is moving towards the wall and observer is also riding the same source.
The velocity of the observer,


It depends on the kind of soda can
The greatest percent of mass of the universe is dark matter
The period of the musical note is
seconds.
Answer: Option A
<u>Explanation:</u>
The frequency is defined as the number of oscillations or a complete cycle of wave occurred in a given time interval. So the frequency is inversely proportional to the time period. Thus the mathematical representation of frequency with time period is

As the frequency is given as
, the time period can be found as

Thus,

Thus the time period for the frequency of the musical note is
seconds.
Answer:
They could lose their magnetism if they are dropped too hard or banging against something (the ground)
Explanation:
the domains may bump out of alignment. hope this helps ! :)