Two boats start together and race across a 60-km-wide lake and back. Boat A goes across at 60 km/h and returns at 60 km/h. Boat B goes across at 30 km/h, and its crew, realizing how far behind it is getting, returns at 90 km/h. Turnaround times are negligible, and the boat that completes the round trip first wins. (a)Which boat wins and by how much? (Or is it a tie?) (b) What is the average velocity of the winning boat?

Explanation:

a) Boat A wins as it crosses the finish line at the same time Boat B makes its turn around.

Say the lake was 60 km wide

Boat A takes a time of 120 km / 60 km/hr = 2 hrs to finish the race

Boat B takes a time of 60/30 + 60/90 = 2 + 2/3 hrs to finish the race

Boat A wins by 60 km or 2/3 hr which is 40 minutes.

In general, Boat A will win by the length of the lake and a significant amount of time.

average velocity of the winning boat is 0 km/hr as velocity is displacement over time. As the start and finish are at the same point, there is no displacement. Average speed, which is distance over time is 60 km/hr.

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explanation:

physics means: "the branch of science concerned with the nature and properties of matter and energy. the subject matter of physics, distinguished from that of chemistry and biology, includes mechanics, heat, light and other radiation, sound, electricity, magnetism, and the structure of atoms."

1 is a answer of a question