Disk A, with a mass of 2.0 kg and a radius of 70 cm , rotates clockwise about a frictionless vertical axle at 20 rev/s . Disk B, also 2.0 kg but with a radius of 30 cm , rotates counterclockwise about that same axle, but at a greater height than disk A, at 20 rev/s . Disk B slides down the axle until it lands on top of disk A, after which they rotate together. Required:
What is their common angular velocity in rev/s, and in which direction do they rotate?

Aman throws a football straight into the air. as it rises, it slows down. which type of energy is the football gaining?

Aspacecraft that renters the earth’s atmosphere drastically slows down. the amount of kinetic energy the spacecraft has as it reenters the earths atmosphere

Which statements identify what astronomers currently know and think will happen with our universe? check all that apply. the big bang produced dark energy, which accounts for some of the energy needed to expand the universe. the vastness of space may contain a type of matter known as "dark matter." the universe is currently shrinking at a rapid rate. the universe is currently expanding at an accelerating rate. the big bang theory explains all the energy and matter discovered by scientists.