Calculating Mass from Acceleration and Net Force

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To calculate the mass of the high jumper, the net force exerted by the foam pit and the jumper's acceleration must be determined using Newton's second law. The average force of -1100 N indicates the force acting against the jumper's weight. The acceleration can be calculated from the jumper's fall speed and the distance compressed in the foam pit. The correct mass is likely closer to 121 kg, as 1845 kg seems implausible given typical human weights. Proper calculations should clarify the mass based on the provided forces and distances.
MissFortune
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This was the original question: A high jumper falling a 3.9 m/s, lands on a foam pit and comes to rest, compressing the pit a distance of 0.43 m. If the pit is able to exert an average fource of -1100 N on the high jumper in breaking the fall, what is the jumper's mass?
But I am not sure if I am supposed to multiply or divide 0.43m and 3.9 m/s
Ive narrowed the answer down to either 1845 kg or 121 kg.
 
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Ive narrowed the answer down to either 1845 kg or 121 kg.

Well, 1845kg is about 4000lbs.. whereas 121kg is about 260lbs..
 
Ive been leaning towards 121kg mainly because of that, but I just wanted to be sure.
 
Show your work and I can look over it.
 
MissFortune said:
But I am not sure if I am supposed to multiply or divide 0.43m and 3.9 m/s
Ive narrowed the answer down to either 1845 kg or 121 kg.
Sounds like you're guessing?

(1) What's the acceleration?
(2) Apply Newton's 2nd law to find the mass. (Use the net force.)
 

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