Calculating Force for an Exceptional Standing Jump: Physics Homework Problem

[PearlyD]

Homework Statement

An exceptional standing jump would raise a person 0.80m off the ground. To do this, what force must a 66 kg person exert against the ground?
Assume the person crouches a distance of 0.20 m prior to jumping,and thus the upward force has this distance to act over before he leaves the ground.



This question i don't even know how to start
can some one explain how to even start it?

 

[nickdk]

Work = Force * Distance
Force = (9.81)(66)
Work = (9.81)(66)(.80)
Work = 517.968 J

Doesn't account for the crouching distance, but it may be irrelevant, someone else will probably cover that. I hope I went in the right direction with this.

 

[kerimek]

Sure, I can explain how to start solving this problem.

First, we need to understand the concept of force. Force is a physical quantity that describes the interaction between two objects. In this case, the force we are interested in is the force exerted by the person on the ground, which is also known as the normal force.

Next, we need to understand the concept of work. Work is defined as the product of force and displacement. In this case, the displacement is the height the person jumps, which is 0.80m.

Using these concepts, we can set up the equation:

Work = Force x Displacement

We know the displacement (0.80m) and we need to find the force. However, we also need to take into account the crouching distance of 0.20m. This means that the person's body will already be 0.20m closer to the ground before they start jumping. So, the total displacement that the force will act over is 0.80m + 0.20m = 1.00m.

Now, we can rearrange the equation to solve for force:

Force = Work / Displacement

Plugging in the known values, we get:

Force = (66 kg x 9.8 m/s^2) / 1.00m

= 646.8 N

Therefore, the force that a 66 kg person must exert against the ground to perform an exceptional standing jump of 0.80m is 646.8 Newtons.

I hope this explanation helps you understand how to approach this problem. Remember, in physics, it's always important to understand the concepts and units involved before plugging in numbers and solving equations.