An empty sled is dragged along a snow covered trail. If the sled was filled with firewood, the force of friction between the sled and the snow would

In a classical model of the hydrogen atom, the electron moves around the proton in a circular orbit of radius 0.053 nm. what is the electron's orbital frequency? what is the effective current of the electron?

Which describes increasing the efficiency of energy resource

Point charges q1=+2.00μc and q2=−2.00μc are placed at adjacent corners of a square for which the length of each side is 1.50 cm . point a is at the center of the square, and point b is at the empty corner closest to q2. take the electric potential to be zero at a distance far from both charges. part a what is the electric potential at point a due to q1 and q2? express your answer with the appropriate units.