Josh has a helium-filled balloon. He wants to calculate the speed of his balloon as it rises to the ceiling. What two measuremen
1 answer:
You might be interested in
Answer:
The temperature of the steam during the heat rejection process is 42.5°C
Explanation:
Given the data in the question;
the maximum temperature T in the cycle is twice the minimum absolute temperature T
in the cycle
T = 0.5T
now, we find the efficiency of the Carnot cycle engine
η = 1 - T
/T
η = 1 - T
/0.5T
η = 0.5
the efficiency of the Carnot heat engine can be expressed as;
η = 1 - W
/Q
where W is net work done, Q
is is the heat supplied
we substitute
0.5 = 60 / Q
Q = 60 / 0.5
Q = 120 kJ
Now, we apply the first law of thermodynamics to the system
W = Q
- Q
60 = 120 - Q
Q = 60 kJ
now, the amount of heat rejection per kg of steam is;
q = Q
/m
we substitute
q = 60/0.025
q = 2400 kJ/kg
which means for 1 kilogram of conversion of saturated vapor to saturated liquid , it takes 2400 kJ/kg of heat ( enthalpy of vaporization)
q = h
= 2400 kJ/kg
now, at h = 2400 kJ/kg from saturated water tables;
T = 40 + ( 45 - 40 ) (
)
T = 40 + (5) × (0.5)
T = 40 + 2.5
T = 42.5°C
Therefore, The temperature of the steam during the heat rejection process is 42.5°C
Answer:
the speed of the block when it reaches point B is 14 m/s
Explanation:
Given that:
mass of the block slides = 1.5 - kg
height = 10 m
Force constant = 200 N/m
distance of rough surface patch = 20 m
coefficient of kinetic friction = 0.15
In order to determine the speed of the block when it reaches point B.
We consider the equation for the energy conservation in the system which can be represented by:
v = 14 m/s
Thus; the speed of the block when it reaches point B is 14 m/s