What is the kinetic energy of an object with a mass of #10 kg# that has been in freefall for #2 s#?

1 Answer
Jan 9, 2016

Answer:

I found #K=1,920,8J#

Explanation:

There are two ways to find this:
1) evaluate the velocity and use, for the kinetic energy, #K=1/2mv^2#;
2) evaluate the potential energy #U# at the start that will be converted into kinetic energy:
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From this:
#U=mgh=10*9.8*19.6=1,920.8J#
This potential energy at the top will be changed entirely into kinetic energy (neglecting friction).