Two objects exert a (conservative) force on each other that is repulsive. For example, the force on object 1 from object 2 points away from object 2. If the two objects move toward each other, does the potential energy of the two objects increase, decrease, or stay the same?
SubsectionA*R*C*S Activities
A*R*C*S8.15.2.Falling Block.
Shown in the figure below are two blocks connected by an ideal string that passes over a massless, frictionless pulley. The mass of the larger block sits on a flat, frictionless table and the smaller block hangs vertically. Use energy analysis to calculate the speed of each block when the larger block reaches the edge of the table after sliding a distance \(L\text{.}\)
Figure8.15.1.
Activity8.15.3.Metacognitive Reflection.
For the activity above, it is possible to use force analysis instead of energy analysis to calculate the speed of each block. You do not have to perform this calculation (you did a similar one in a previous chapter), but write a brief description of the steps that would be involved in this solution. Compare and contrast those steps to the energy analysis steps you carried out. Which kind of analysis do you think is simpler for a situation like this?
