Answer:
η = 40 %
Explanation:
Given that
Qa ,Heat addition= 1000 J
Qr,Heat rejection= 600 J
Work done ,W= 400 J
We know that ,efficiency of a engine given as

Now by putting the values in the above equation ,then we get

η = 0.4
The efficiency in percentage is given as
η = 0.4 x 100 %
η = 40 %
Therefore the answer will be 40%.
Momentum
= mass x velocity
= 0.2 x 5
= 1 kg m/s
D because choppy water is already a little bit of wave action and then the wind adds a lot of speed to the waves and height to the waves to meek the best waves. Hope this helped.
Gravitational force on a satellite is given by the formula

now here we know that force on the satellite is F when its distance from center of Earth is R
Now the distance from the center of earth will be 3R so the force is given as


so if we compare it with initial value of force then it is

so correct answer is
