Air resistance is a nonconservative force. it always opposes the motion of an object. an airplane flies from new york to atlanta and then returns to its point of departure. the net work done by air resistance during this round trip
a) is negative for slower speeds and positive for higher speeds
b) is positive
c) is negative
d)is zero
e) is negative for higher speeds and positive for slower speeds

the second one and the forth one are in the purple because they are opinions and the rest are in the yellow

explanation:

acceleration = (change in speed) / (time for the change)

change in speed = (20-120)= -100 m/s.

1.5 min = 90 sec

acceleration = -100/90 = -1.11 m/s^2.

we don't care about the 150kg or the 2,500 meters. they don't make any difference.

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the body's situation won't change the forces are equal opposit and on the same body