Objects tend to come to rest at a position of lowest potential
energy. Think of a machine or system that works against this
tendency. Describe how kinetic energy is needed to increase
the system's potential energy.

Most energy in an ecosystem comes originally from_

The uniform slender bar rests on a smooth horizon- tal surface when a force f is applied normal to the bar at point a. point a is observed to have an initial acceleration aa of 20 m/s2, and the bar has a corre- sponding angular acceleration of 18 rad /s2. deter- mine the distance b.

What is the major limitation to the light microscope?