Acceleration

by Mr. Krall

What is acceleration?

Acceleration tells how quickly an object changes velocity.

When the voice on a commercial says a sports car… “Goes from zero to 60 in 3

seconds.” That’s acceleration.

Acceleration causes the feeling you get when the roller coaster starts dropping

down the big hill.

Acceleration tells if something will “stop on a dime” or “grind to a halt.”

When the bus driver steps on the gas and the bus s l o o o w ly gets up to speed. That’s a low acceleration.

How much longer until we are going the speed limit?

Zip it, kid.

TYPICALUNLIKELY

AAAAAHHHH!!HELP US!

Zip it, kid.

The formula for acceleration is:

the velocity the object is going at the end (VFINAL) – the velocity the object was going when it started (VINITIAL)

the amount of time the object was accelerating (T)

= acceleration (A)

VFINAL – VINITIAL

T

= A

The number you get from an acceleration problem answers this question:

“How much does the object’s velocity change for each unit of time that passes?”

So an acceleration of 5 miles/hour/second means:

5 miles/hour/second“For every second that goes by, the objects’ velocity increases by 5 miles/hour.”