Answer: The answer is density
If you are involved in a collision, it's important that you stop your car and protect others, as well as your self, from oncoming traffic. If you do not stop, you will have an arrest warrant against your name as it can safely be considered a 'hit and run.'
I'm not sure. But it can be A or C.
Answer:
32%
Explanation:
For a heat engine, efficiency is work out divided by heat in:
η = Wₒ / Qᵢ
Since energy is balanced, heat in is the sum of work out and heat out:
Qᵢ = Wₒ + Qₒ
Therefore:
η = Wₒ / (Wₒ + Qₒ)
Given Wₒ = 710 J and Qₒ = 1480 J:
η = 710 / (710 + 1480)
η = 0.32
The thermal efficiency is 32%.
A. Upstream refers to the motion of the swimmer where he is against the current. The resultant speed of the swimmer is equal to the difference of the velocity or speed in still water and that of the river. The time it requires to cover the distance is calculated through the equation,
t = d / s
where t is time, d is distance, and s is speed. Substituting the known values,
t = 1000 m / (1.2 m/s - 0.5 m/s) = 1,428.57 seconds
(b) The time it requires for the swimmer to swim in still water,
t = 1000 m / (1.2 m/s) = 833.33 seconds
(c) Intuitively, it takes longer to cover the distance when there is current because the current will serve as resistance to the motion of the swimmer, partially moving it backwards instead of forward.
