A sprinter who is running a 250 m race accelerates from rest at 7.5 m/s² for 1.2 s and maintains this speed for the remainder of the race. What is her time for the race?

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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an electric circuit

pythagoras' theorem

square root (-5^2+9^2)

square root (25+81)

square root (106)

angle is tan^-1(9/5)

neg x, pos y

the ima (higher than 1m) will be greater than the ima with the height of 1m.