Which of these is true about pure substances? A. They can only contain one type of molecule.

B. They can contain different types of atoms and molecules.

C. They may contain one type of atom or one type of molecule.

D. They can only contain one type of atom.

Can somebody explain to me how newton's 3rd law relates to momentum? ~ap physics 1

In a heat engine if 1000 j of heat enters the system the piston does 500 j of work, what is the final internal energy of the system if the initial energy was 2000 j? 1. write the equation 2.list out your known variables 3.plug the numbers into the equations 4.solve 5.write your solution statement that includes initial energy and final

Greg drew a diagram to compare two of the fundamental forces. which labels belong in the areas marked x, y and z? gravitational force electromagnetic force x. attractive y repulsive z: infinite range x: infinite range y attractive z. repulsive x. always attractive y: infinite range z: attractive or repulsive x. attractive or repulsive y infinite range z: always attractive