A bus is travelling at 10m/s. It accelerates at 2m/s^2 over a distance of 20m. Calculate it's final velocity

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

Achlorine atom has 17 protons and 18 neutrons. what is its mass number? what is its atomic number?

Students in an introductory physics lab are performing an experiment with a parallel-plate capacitor made of two circular aluminum plates, each 11 cm in diameter, separated by 1.0 cm. how much charge can be added to each of the plates before a spark jumps between the two plates? for such flat electrodes, assume that value of 3×106n/c of the field causes a spark.