Answer:

Explanation:
Given that,
The position of a particle is given by :

Let us assume we need to find its velocity.
We know that,

So, the velocity of the particle is
.
Transformation of energy, because energy cannot be created or destroyed
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Answer:
From the First Law of Motion
Vf = Vi + at
"It reaches a speed of 52m/s" meaning the Final speed Vf=52
a(acceleration)=10m/s²
t=4s
Applying the formula
52=Vi + 10(4)
Vi = 52-40
Vi = 12m/s
Assuming an ideal gas, the speed of sound depends on temperature
only. Air is almost an ideal gas.
Assuming the temperature of 25°C in a "standard atmosphere", the
density of air is 1.1644 kg/m3, and the speed of sound is 346.13 m/s.
The velocity can't be specified, since the question gives no information
regarding the direction of the sound.