An unknown element has 5 protons, 5 electrons, and 6 neutrons what is the atomic mass of this element

The law of the conservation of momentum says that the total momentum of any closed and isolated system cannot

What pressure difference is required between the ends of a 2.0-m-long, 1.0-mm-diameter horizontal tube for 40 c water to flow through it at an average speed of 4.0 m/s?

What efficiency of a car's engine when heat input is 200,000 joules and waste heat is 150,000 joules? a. 75% b. 35% c. 25% d. 85%