Answer:
The value is 
Explanation:
From the question we are told that
The work input is
The heat delivered is 
The value of A is A = 14
The value of B is B = 72
Generally the efficiency of the heat engine is mathematically represented as

Here
is the total out energy produce by the heat engine and this is mathematically represented as

=> 
=> 
So

=> 
=> 
=> 
Answer:
(a) Vf = 128 ft/s
(b) K.E = 122.8 Btu
Explanation:
(a)
In order to find the velocity of the object just before striking the surface of earth or the final velocity, we use 3rd equation of motion:
2gh = Vf² - Vi²
where,
g = 32.2 ft/s²
h = height = 253 ft
Vf = Final Velocity = ?
Vi = Initial Velocity = 10 ft/s
Therefore,
(2)(32.2 ft/s²)(253 ft) = Vf² - (10 ft/s)²
16293.2 ft²/s² + 100 ft²/s² = Vf²
Vf = √(16393.2 ft²/s²)
<u>Vf = 128 ft/s</u>
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(b)
The kinetic energy of the object before it hits the surface of earth is given by:
K.E = (0.5)(m)(Vf)²
where,
m = mass of object = 375 lb
K.E = Kinetic energy of object before it strikes the surface of earth = ?
Therefore,
K.E = (0.5)(375 lb)(128 ft/s)²
K.E = 3073725 lb.ft²/s²
Now, converting this to Btu:
K.E = (3073725 lb.ft²/s²)(1 Btu/25037 lb.ft²/s²)
<u>K.E = 122.8 Btu</u>
Answer:
Magneta is a mix of blue and red and is a secondary colour.
Explanation:
As we can see green is the complementary colour of Magneta.Complementary colours are the pairs of colours which when combined cancel each other out. This means that when combined they produce a grayscale colour like white or black .
Answer:
light doesn't need a medium through which to travel because the speed of light is experimentally constant