What is the mass of an object that needs a 4000 n to accelerate it at a rate of 10m/sec2

Identify two factors that determine the rate of stream erosion

Arigid tank is divided into two equal parts by a partition. one part of the tank contains 3 kg of compressed liquid water at 400 kpa and 60°c while the other part is evacuated. the partition is now removed, and the water expands to fill the entire tank. determine the entropy change of water during this process, if the final pressure in the tank is 40 kpa. use steam tables.

This is the number of complete movements of a wave per second.