Which of the following must be true in order for an object to stay in place? The forces must be balanced.
The forces must be positive.
The forces must be negative.
The forces must be gravitational.

Matter that emits no light at any wavelength is called

What is the gravitational attraction between a dating couple whose centers of mass are 0.630 m apart if the boy weighs 715 n and the girl weighs 465 n?

While carrying a heavy box up the stairs,you set the box on a step and rest. then you pick up the box and carry it to the top of the stairs. describe these actions in terms of balanced and unbalanced forces acting on the box.