Getting going is acceleration
Photograph by Amber Wiener

Whenever a velocity changes, we say that an acceleration is taking place. This includes the cases that the object is speeding up, slowing down, or changing the direction of its motion.

Main pages in this section	Estimated time required
Rolling Downhill	20 minutes
Rolling Down Hill, Part 2	45 minutes
Science content: Acceleration	30 minutes
Discussion of the unit on Acceleration	30 minutes

Materials needed for this section

• Force scale*
• board with hook *
• track section *
• steel ball *
• measuring tape *
• stop watch *
• arrow markers *

Supplementary material:

Why study acceleration?
Next section:More about acceleration