Explanation:
Formula for maximum efficiency of a Carnot refrigerator is as follows.
..... (1)
And, formula for maximum efficiency of Carnot refrigerator is as follows.
...... (2)
Now, equating both equations (1) and (2) as follows.
=

= 
= 
= 2.5
Thus, we can conclude that the ratio of heat extracted by the refrigerator ("cooling load") to the heat delivered to the engine ("heating load") is 2.5.
Fossil fuels have led to an increase in food costs.
Explanation:
Buried organic material over million of years form combustible geologic deposits of organic materials called fossil fuels that can be converted crude oil, natural gas, or coal.
Fossil fuel are currently used as a source of energy in machine and equipment applied in the farming industry. Mechanization has been made possible due to this type of fuel availability thus larger farms have been prepared for cultivation.In addition, other processes such as planting,weeding and harvesting are currently performed by farming machines which are propelled by fossil energy. So in general, fossil fuels in the farming industry has led to increase in amount of crop harvested because more farms are under cultivation and farming process is now mechanized. However, due to use of machines and energy, the production cost has increased, thus to cover for this increased cost, the prices for food products increases, making the cost of food commodities to rise.
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Fossil fuels: brainly.com/question/13660400
Keyword: Farming, industry, fossil fuel
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Answer:
a) a = 34.375 m / s², b) v_f = 550 m / s
Explanation:
This problem is the launch of projectiles, they tell us to ignore the effect of the friction force.
a) Let's start with the final part of the movement, which is carried out from t= 16 s with constant speed
v_f =
we substitute the values
v_f =
The initial part of the movement is carried out with acceleration
v_f = v₀ + a t
x₁ = x₀ + v₀ t + ½ a t²
the rocket starts from rest v₀ = 0 with an initial height x₀ = 0
x₁ = ½ a t²
v_f = a t
we substitute the values
x₁ = 1/2 a 16²
x₁ = 128 a
v_f = 16 a
let's write our system of equations
v_f =
x₁ = 128 a
v_f = 16 a
we substitute in the first equation
16 a =
16 4 a = 6600 - 128 a
a (64 + 128) = 6600
a = 6600/192
a = 34.375 m / s²
b) let's find the time to reach this height
x = ½ to t²
t² = 2y / a
t² = 2 5100 / 34.375
t² = 296.72
t = 17.2 s
We can see that for this time the acceleration is zero, so the rocket is in the constant velocity part
v_f = 16 a
v_f = 16 34.375
v_f = 550 m / s
Answer:
C
Explanation:
The sun has rotated causing the shadow to reflect.