Acceleration

Problem : A jet begins it's flight in New Jersey and can accelerate off the runway at 500 meters per second Southwest 10 seconds. However, the jet's velocity slows down to approach the runway to 300 meters per second squared.

Acceleration as a Rate Acceleration is more than just changing velocity. It is a rate that measures the change in velocity per unit of time. This rate tells you how quickly (or how slowly) an object’s velocity changes over time. The more quickly an object changes speed or direction, the greater its acceleration.

An object’s acceleration can change from moment to moment, just like its velocity can. However, you can calculate an object’s average acceleration. First subtract its starting velocity from its ending velocity. Then divide that result by the time over which the change in velocity happened. Written as an equation, acceleration is:

average acceleration= ending velocity − starting velocity / time

When you look at the equation, you can see that acceleration has units of velocity divided by units of time. A common unit of velocity is meters per second (m/s) and a common unit of time is seconds (s). Thus, a common unit of acceleration is meters per second per second ((m/s)/s), which is also written as meters per second squared (m/s2).

Example : average acceleration= 6 m/s − 0 m/s / 3 s = 2 m/s2

The car’s speed increases by 2 m/s every second. The car in the picture before starts with a velocity of 6 m/s and slows to a velocity of 0 m/s in 3 seconds.