We can solve the problem by using the first law of thermodynamics, which states that:

where

is the change in internal energy of the system
Q is the heat absorbed by the system
W is the work done by the system
In our problem, the heat absorbed by the system is Q=+194 kJ, while the work done is W=-120 kJ, where the negative sign means the work is done by the surroundings on the system. Therefore, the variation of internal energy is
Answer:
50.3N
Explanation:
Work done = force x distance
422J. = force x 8.39m
÷8.39 both side to get force
Force is 50.3N to 1 d.p.
Check:
50.3 x 8.39=422.017J
Same as 422J to 1 d.p
Given Information:
Wavelength = λ = 39.1 cm = 0.391 m
speed of sound = v = 344 m/s
linear density = μ = 0.660 g/m = 0.00066 kg/m
tension = T = 160 N
Required Information:
Length of the vibrating string = L = ?
Answer:
Length of the vibrating string = 0.28 m
Explanation:
The frequency of beautiful note is
f = v/λ
f = 344/0.391
f = 879.79 Hz
As we know, the speed of the wave is
v = √T/μ
v = √160/0.00066
v = 492.36 m/s
The wavelength of the string is
λ = v/f
λ = 492.36/879.79
λ = 0.5596 m
and finally the length of the vibrating string is
λ = 2L
L = λ/2
L = 0.5596/2
L = 0.28 m
Therefore, the vibrating section of the violin string is 0.28 m long.
Explanation:
Below is an attachment containing the solution.
This is fairly easy. The earlier view of the solar system (geocentric) was all based on how other planets and the sun were constantly revolving the earth and we were completely stationary. The Heliocentric view has been proved to be accurate, and it is that the sun is stationary and the planets are revolving it. The similarities are that in that time, it was a continued belief that the planets were the Roman Gods, i.e. Jupiter, Neptune. Another thing is that they were correct in the Geocentric theory with the thought that the planets revolved around something.