Explanation:
It is known that energy balance relation is as follows.
Also, 
so, 
According to the ideal gas equation,
Putting the values into the above equation as follows.
= 
= 693.3 R
Now, we will convert the temperature into degree Fahrenheit as follows.
693.3 - 458.67
= 
From table A-
= 0.240 Btu/lbm R and 
= 0.171 Btu/lbm
Now, we will substitute the energy balance as follows.
= 
= 59.3 Btu
Thus, we can conclude that final temperature of air is 59.3 Btu.
Gravity pulls the water down off the mountain, witch is run-off.
Power is the rate at which work is done (2nd option)
Given parameters:
Acceleration of the car = 1.6m/s
Initial speed = 80km/hr
Final speed = 110km/hr
Solution:
Time taken to achieve this speed = ?
Solution:
Acceleration is the rate of change of velocity with the time taken.
Mathematically;
a = 
where a is the acceleration
V is the final velocity
U is the initial velocity
T is the time taken
Now make the unknown time the subject of the expression;
aT = V - U
T = 
Convert the given acceleration to km/hr;
1.6m/s = 1.6 x 
x 
x 
= 5.76km/hr
Input the parameters and solve;
T = 
= 5.2hrs
The time taken is 5.2hrs
Here we go.
My abbreviations; KE = Kinetic Energy; GPE = Gravitational Potential Energy.
So first off, we know the fish has KE right when the bird releases it. Why? Because it has horizontal velocity after released! So let’s calculate it:
KE = 1/2(m)(V)^2
KE = 1/2(2)(18)^2
KE = 324 J
Nice!
We also know that the fish has GPE at its maximum height before release:
GPE = mgh
GPE = (2)(9.81)(5.40)
GPE = 105.95 J
Now, based on the *queue dramatic voice* LAW OF CONSERVATION OF ENERGY, we know all of the initial energy of the fish will be equal to the amount of final energy. And since the only form of energy when it hits the water is KE, we can write:
KEi + GPEi = KEf
(Remember - we found the initial energies before!)
(324) + (105.95) = KEf
KEf = 429.95J
And that’s you’re final answer! Notice how this value is MORE than the initial KE from before (324 J) - this is because all of the initial GPE from before was transformed into more KE as the fish fell (h decreased) and sped up (V increased).
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