The answer is A. <span>Some work input is used to overcome friction. </span>
We know that the average speed is simply the ratio of the
total distance travelled over the total duration of the trip.
total distance = 500 mi + 380 mi + 600 mi
total distance = 1,480 mi
total time = 10 h + 8 h + 15 h
total time = 33 h
So the average speed is therefore:
average speed = 1,480 mi / 33 h
<span>average speed = 44.85 mi / h</span>
The source and the observer are moving towards each other. The observer is moving toward the source. The source is moving away from the observer
Answer:
Without it, we could not survive on Earth. Earth orbits the sun due to the gravity of the sun, which maintains us at a convenient distance from it to enjoy the sun's warmth and light. It keeps the air we need to breathe and our atmosphere in place. Our planet is held together by gravity.