Answer:
50%
Explanation:
Efficiency = work out / work in
e = Fd / W
e = (2000 N) (2 m) / (8000 J)
e = 0.5
Answer:
Approximately .
Explanation:
Consider two objects of mass and . Let denote the distance between the center of mass of each object. Let denote the gravitational constant. (.)
By Newton's Law of Universal Gravitation, the size of gravitational attraction between these two objects would be:
.
In this question, and are the mass of the two planets. The distance between the two planets is (approximately the same as the distance between the center of mass of planet Earth and the center of mass of Mars.)
Apply Newton's Law of Universal Gravitation to find the size of gravitational attraction between the two planets:
.
Since , the size of gravitational attraction between the two planets would be approximately .
Answer:
A
Explanation:
circulatoy system and respiratory
Answer:
dam/hydro power
Explanation:
estuary is the place where rivers meet the ocean, there are a lot of currents there (waves...) so it likely means thery use a dam or some sort of way of collecting electricity from the motion of the water there. many birds live in estuaries because of being able to find fish to feed from