Answer:
We know ForceF=mass×acceleration----------(1)
And given ForceF=
r
mv
2
----------(2)
Equating 1 and 2 dimensionaly we get ,
ma=
r
mv
2
MLT
−2
=ML
2
T
−2
L
−1
MLT
−2
=MLT
−2
<span>The nickel has a mass of approximately 0.005kg</span>
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,


Katherine paid $1.25 for a bottle of water