Confusing (but surely simple) gravity problem

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To determine the constant force a 70kg person must exert to achieve a vertical jump of 0.80m, the initial velocity needed for the jump must be calculated using gravitational acceleration. The person also lowers themselves 0.20m before jumping, which affects the force exerted. The net force can be derived from the equation F(net) = ma, where 'm' is mass and 'a' is acceleration. The discussion references a similar problem for additional guidance. Understanding the relationship between jump height, velocity, and force is crucial for solving this gravity problem.
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Homework Statement



An exceptional vertical jump from rest would raise a person 0.80m off the ground. To do this, what constant force would a 70kg person have to exert against the ground? Assume the person lowers himself 0.20m prior to jumping and remains in a standing position while in the air.

Homework Equations



F(net)=ma?


The Attempt at a Solution



Not a clue...
 
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It's easy to say: "Not a clue..." :smile:

Maybe https://www.physicsforums.com/showthread.php?t=225490" will help (as it already did). It's almost the same.

You need the velocity at which man must leave the ground to reach the height of 0.8 m (you know the g). Therefore you can calculate the acceleration and the force.
 
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Lol, thank you soooo much (again!)
 

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