Answer:
The change in internal energy of the system is -17746.78 J
Explanation:
Given that,
Pressure 
Remove heat 
Radius = 0.272 m
Distance d = 0.163 m
We need to calculate the internal energy
Using thermodynamics first equation
...(I)
Where, dU = internal energy
Q = heat
W = work done
Put the value of W in equation (I)

Where, W = PdV
Put the value in the equation


Hence, The change in internal energy of the system is -17746.78 J
The period is the time taken by the wave to complete an oscillation. The frequency of the given sound is 500 Hz.
<h2>
Period:</h2>
It is the time taken by the wave to complete an oscillation. The frequency is inversely proportional to the time:

Where,
- frequency
- period = 0.002 s
Put the value in the equation,

Therefore, the frequency of the given sound is 500 Hz.
Learn more about Period:
brainly.com/question/842349
Answer:
22 km/h
Explanation:
Given that,
Speed of Xavier, v = 14 km/h
He tosses a set of keys forward on the ground at 8 km/h, v' = 8 km/h
We need to find the speed of the keys relative to the ground. Let it is V.
As both Xavier and the keys are moving in same diretion. The relative speed wrt ground is given by :
V = v+v'
V= 14 + 8
V = 22 km/h
So, the speed of the keys relative to the ground is 22 km/h.