Starting from rest, a 5.0 kg block slides 2.5 m down a rough 30.0° incline in 2.0 s. Determine the following
a. the work done by the force of gravity
b. the mechanical energy lost due to friction
C. the work done by the normal force between the
block and the incline

These models show the electron structures of two different nonmetal elements. which element is likely more reactive, and why? element 1 is more reactive because it has fewer electron shells and is toward the top of its group on the periodic table. element 1 is more reactive because it has more electrons in its valence shell and is farther to the right on the periodic table. element 2 is more reactive because it does not have a valence shell close to the nucleus, so it will attract electrons. element 2 is more reactive because it does not have a full valence shell, so it will attract electrons.

The percent efficiency of a machine can never be 100% (or greater), because in the real world some energy is always converted into a. heat b. work c. input force d. output force

If a tank filled with water contains a block and the height of the water above point a within the block is 0.8 meter, what is the pressure at point a?