Physics
Physics Forces
Quick fact
The word 'force' comes from the Latin 'fortis,' meaning strong. In physics, the standard unit of force is the newton (N), named after Sir Isaac Newton. One newton is roughly the force needed to hold a small apple in your hand.
Why this is interesting
Why does a ball keep rolling unless you stop it, but a book sitting on a table stays perfectly still? What invisible push or pull decides whether something moves or stays put?