Asample of blood is placed in a centrifuge of radius 12.0 cm. the mass of a red blood cell is 3.0 ✕ 10^−16 kg, and the magnitude of the force acting on it as it settles out of the plasma is 4.0 ✕ 10^−11 n. at how many revolutions per second should the centrifuge be operated?

What is the internal energy of 4.00 mol of diatomic nitrogen gas n2 at 455k

Give one example to show that when substances are mixed,it may result in a chemical or a physical change depending on the conditions.

Two identical stars with mass m orbit around their center of mass. each orbit is circular and has radius r, so that the two stars are always on opposite sides of the circle. (a) find the gravitational force of one star on the other. (b) find the orbital speed of each star and the period of the orbit. (c) how much energy would be required to separate the two stars to infinity?