A small object with mass
m = 0.0900 kg
moves
along the +x-axis. The only force on the object is a conservative
force that has the potential-energy function U(x) = -x^{2} + x^{3},
where
=
6.00 J/m^{2}
and
J/m^{3} = 0.300 x.
The object is released
from rest at small x.

When the object is at
x = 4.00 m, what is its speed?

When the object is at
x = 4.00 m, what is the magnitude of its acceleration?

When the object is at
x = 4.00 m, what is the direction of its acceleration?

What is
the maximum value of x reached by the object during its motion?