Abag is dropped from a hovering helicopter. when the bag has fallen 2 seconds,
a. what is the bag's velocity?
b. how far has the bag fallen?

In a system, when potential energy decreases, then entropy also decreases. true false

Examine the equation. 23490th→23088ra+42he what kind of barrier would you need to block the radioactive particles from this reaction? a.a piece of paper b.a sheet of aluminum foil c. a two-inch block of lead d. a solid concrete block

An object weigh 40n in air ,weigh 20n when submerged in water,and 30n when submerged in a liquid of unknown liquid density.what is the density of unknown of liquid?