It is right have a good day
explanation step by step
Answer:
the claim is not valid or reasonable.
Explanation:
In order to test the claim we will find the maximum and actual efficiencies. maximum efficiency of a heat engine can be found as:
η(max) = 1 - T₁/T₂
where,
η(max) = maximum efficiency = ?
T₁ = Sink Temperature = 300 K
T₂ = Source Temperature = 400 K
Therefore,
η(max) = 1 - 300 K/400 K
η(max) = 0.25 = 25%
Now, we calculate the actual frequency of the engine:
η = W/Q
where,
W = Net Work = 250 KJ
Q = Heat Received = 750 KJ
Therefore,
η = 250 KJ/750 KJ
η = 0.333 = 33.3 %
η > η(max)
The actual efficiency of a heat engine can never be greater than its Carnot efficiency or the maximum efficiency.
<u>Therefore, the claim is not valid or reasonable.</u>
Answer:
The system loses 90 kJ of heat
Explanation:
We can answer the question by using the 1st law of thermodynamics, which states that:
where
is the change in internal energy of the system
is the heat absorbed by the system (positive if absorbed, negative if released by the system)
is the work done by the system (positive if done by the system, negative if done by the surrounding on the system)
In this problem, we have:
is the work done (negative, because it is done by the surrounding on the system)
is the increase in internal energy
Using the equation above, we can find Q, the heat absorbed/released by the system:
And the negative sign means that the system has lost this heat.
<u>Answer</u>
1) A. 96 Candelas
2) A. Both of these types of lenses have the ability to produce upright images.
3) C. 5 meters
<u>Explanation</u>
Q1
The formula for calculation the luminous intensity is;
Luminous intensity = illuminance × square radius
Lv = Ev × r²
= 6 × 4²
= 6 × 16
= 96 Candelabra
Q2
For converging lenses, an upright image is formed when the object is between the lens and the principal focus while a diverging lens always forms and upright image.
A. Both of these types of lenses have the ability to produce upright images.
Q3
Luminous intensity = illuminance × square radius
square radius = Luminous intensity/ illuminance
r² = 100/4
= 25
r = √25
= 5 m
