Answer:
56 kg
Explanation:
The change in potential energy of the man is given by:
[tex]\Delta U = mg \Delta h[/tex]
where
m is the man's mass
g is the gravitational acceleration
[tex]\Delta h[/tex] is the change in height of the man
In this problem, we have:
[tex]\Delta U=4620 J[/tex] is the gain in potential energy
g = 9.8 m/s^2 is the gravitational acceleration
[tex]\Delta h=8.4 m[/tex] is the change in height
Re-arranging the equation and substituting the numbers, we find the mass:
[tex]m=\frac{\Delta U}{g\Delta h}=\frac{4620 J}{(9.8 m/s^2)(8.4 m)}=56 kg[/tex]
