Answer:
The frequency of the piano string is <em>1059 Hz</em>.
Explanation:
The frequency beat (fb), 2 beats/second, is the absolute difference between the frequency of the tuning fork (1056 Hz) and the frequency of the piano string.
As the piano string gets tightened, the frequency beat becomes 3 beats/second.
Therefore,
fb = 
<span>Hooke's law is F=-kx, which means the elastic force contained by the spring is a product of the distance it stretches and its spring constant, but the direction of the force is opposite that of the displacement. We calculate as follows:
</span><span>(3 kg)(9.8 m/s^2) = -k(-0.38 m)
</span>k =<span> 77.4
</span><span>Then use k to find the new displacement, again using Hooke's law:
(7 kg)(9.8 m/s^2) = -(77.4)x
x = -0.89 m</span>
Answer:


Explanation:
Average power for the human sprinter is given as

so we have



Average power for greyhound is given as



D.N(Newton) this is the S.I unit for force
Pressure and heat. I hope this helps