Answer :
This question involves the concepts of potential energy and work.
"Mr. Gabby" is working the hardest.
Who is working the hardest?
In this case, the work done by each person is equal to the potential energy produced by raising the barbell.
[tex]W = P.E=mgh[/tex]
where,
- W = work done
- m = mass of barbell
- g = acceleration due to gravity = 9.81 m/s²
- h = height raised
For Mr. b
- m = 50 kg
- h = 4 m
Therefore,
[tex]W=(50\ kg)(9.81\ m/s^2)(4\ m)\\W=1962\ J[/tex]
For Mr. Kayla
- m = 45 kg
- h = 7 m
Therefore,
[tex]W=(45\ kg)(9.81\ m/s^2)(7\ m)\\W=3090.15\ J[/tex]
For Mr. Gabby
- m = 47 kg
- h = 8 m
Therefore,
[tex]W=(47\ kg)(9.81\ m/s^2)(8\ m)\\W=3688.56\ J[/tex]
It is clear that most work is done by Mr. Gabby.
Learn more about potential energy here:
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