Oil tends to float on water because the density of oil is the density of water.

What is the measure of a change in an objects velocity?

What is the force that opposes motion and works against the downward pull? a) friction b) gravity c) weight d) acceleration

Aprotein molecule in an electrophoresis gel has a negative charge. the exact charge depends on the ph of the solution, but 30 excess electrons is typical. what is the magnitude of the electric force on a protein with this charge in a 1600n/c electric field? write in two significant numbers, and also in newton