If a 20kg object is moved across the floor and the coefficient of friction is 0.255. what is the frictional force?

Astudent wears sunglasses to her read a book more easily which wave interaction occurs as light passes from the air into the plastic lenses? a polarization b.refraction c.diffraction d. interference

Use henry's law and the solubilities given below to calculate the total volume of nitrogen and oxygen gas that should bubble out of 1.7 l of water upon warming from 25 ˚c to 50 ˚c. assume that the water is initially saturated with nitrogen and oxygen gas at 25 ˚c and a total pressure of 1.0 atm. assume that the gas bubbles out at a temperature of 50 ˚c. the solubility of oxygen gas at 50 ˚c is 27.8 mg/l at an oxygen pressure of 1.00 atm. the solubility of nitrogen gas at 50 ˚c is 14.6 mg/l at a nitrogen pressure of 1.00 atm. assume that the air above the water contains an oxygen partial pressure of 0.21 atm and a nitrogen partial pressure of 0.78 atm.

Make a drawing of the electric field lines around a positive charge, then make a second drawing of the electric field lines around a negative charge.