What is the proper formula used to calculate acceleration?
There are a few. The most famous is a = F/m, where F is the net force applied to a mass, m. Acceleration is also the alter in velocity, Delta-V, divided by the change in time, Delta-t. So, a = Δv/Δt. For example, if an object's velocity alters from 10 meters per second to 20 meters per second in five seconds, its acceleration is (20-10)/5 = 2 meters per second per second, or 2 meters per second squared (m/s2).