Actually Welcome to the concept of Efficiency.
Here we can see that, the Input work is given as 2.2 x 10^7 J and the efficiency is given as 22%
The efficiency is => 22% => 22/100.
so we get as,
E = W(output) /W(input)
hence, W(output) = E x W(input)
so we get as,
W(output) = (22/100) x 2.2 x 10^7
=> W(output) = 0.22 x 2.2 x 10^7 => 0.484 x 10^7
hence, W(output) = 4.84 x 10^6 J
The useful work done on the mass is 4.84 x 10^6 J
The mass of water that must be raised is
Explanation:
Since the process is 70% efficiency, the power in output to the turbine can be written as
where is the power in input.
The power in input can be written as
where
W is the work done in lifting the water
t = 3 h = 10,800 s is the time elapsed
The work done in lifting the water is given by
where
m is the mass of water
is the acceleration of gravity
h = 45 m is the height at which the water is lifted
Combining the three equations together, we get:
Where
And solving for m, we find:
Learn more about power:
#LearnwithBrainly
Answer:
Impulse of force = -80 Ns
Explanation:
<u>Given the following data;</u>
Mass = 50kg
Initial velocity = 1.6m/s
Since she glides to a stop, her final velocity equals to zero (0).
Now, we would find the change in velocity.
Substituting into the equation above;
Change in velocity = 0 - 1.6 = 1.6m/s
Substituting into the equation, we have;
<em>Impulse of force = -80 Ns</em>
<em>Therefore, the impulse of the force that stops her is -80 Newton-seconds and it has a negative value because it is working in an opposite direction, thus, bringing her to a stop. </em>