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ballerina_tee
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[SOLVED] Acceleration, displacement, Kinematics Question
1. Superwoman is hovering above the ground when a person free-falling goes by her at a terminal velocity of 140 km/h. Unforunately, the parachute does not open. Forunately, Superwoman is around. If it takes her 1.9 s to realize the person is in distress, what mus her acceleration be if she is to catch the parachutist just before she hits the ground 1000 m below?
2. I think you use the equation d= v*t + 0.5 a*t^2 and rearrange for a which i got as a=d-v*t/ t^2
3. So I plugged in the numbers given in the question
a=d-v*t/ t^2
= (1000m) -(38.89) (1.9) / 1.9^2
=926.1/3.61
=256 m/s^2
That doesn't look right to me. The answer is supposed to be 3.53 m/s^2. I have no clue what I'm doing wrong! =( Please help! TIA.
1. Superwoman is hovering above the ground when a person free-falling goes by her at a terminal velocity of 140 km/h. Unforunately, the parachute does not open. Forunately, Superwoman is around. If it takes her 1.9 s to realize the person is in distress, what mus her acceleration be if she is to catch the parachutist just before she hits the ground 1000 m below?
2. I think you use the equation d= v*t + 0.5 a*t^2 and rearrange for a which i got as a=d-v*t/ t^2
3. So I plugged in the numbers given in the question
a=d-v*t/ t^2
= (1000m) -(38.89) (1.9) / 1.9^2
=926.1/3.61
=256 m/s^2
That doesn't look right to me. The answer is supposed to be 3.53 m/s^2. I have no clue what I'm doing wrong! =( Please help! TIA.