Physics question (kinetic energy) to all that apply

AI Thread Summary
To calculate the kinetic energy of a 2.0 kg coconut falling from a height of 15 m, the conservation of mechanical energy principle is applicable. The potential energy at the top can be calculated using the formula mgh, while the kinetic energy at impact is given by K=1/2 mv^2. Since the coconut starts from rest, initial velocity (Vo) is zero, and the final velocity can be determined using kinematics. Both conservation of energy and kinematics formulas can be used to solve the problem effectively. Ultimately, either method will yield the same results for the coconut's speed and kinetic energy upon hitting the ground.
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Regarding what formula to use and how exactly is it modified to fit this problem:

A 2.0KG coconut (initially at rest) falls from the top of a coconut tree 15 m high. What is the coconut's kinetic energy when it hits the ground? What is its speed?

I went ahead and drew it out. I'm thinking I can use formulas for potential energy and kinetic. K=1/2 mv^2 and mg(z1-z2); still trying to figure out how to set it up,
thanks for reading this,
Jason
 
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Seems to me like it's a Conservation of Mechanical Energy problem,

Kinetic Energy is always [In Classical Physics] 1/2*m*v^2
Potential Energy here will be from gravity, mgh.

It has two points you can use, when it starts (Vo =0) and when it hits the ground (h=0).
 
Kinematics formulas will also work. You have initial velocity, acceleration, vertical distance, now find final velocity, then use that to find kinetic energy. Since this is probably in an Energy unit, though, you might want to stick to conservation of mechanical energy. Both methods work.
 
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