Answer:
1.3 m
Explanation:
The work done in lifting the backpack is equal to the change in gravitational potential energy of the backpack, so:
[tex]\Delta U=W \Delta h[/tex]
where
W = 100 N is the weight of the backpack
[tex]\Delta h[/tex] is the change in heigth of the object
In this problem, we know that
[tex]\Delta U = 130 J[/tex]
so we can re-arrange the equation to find the change in height of the backpack:
[tex]\Delta h = \frac{\Delta U}{W}=\frac{130 J}{100 N}=1.3 m[/tex]
