Grade 11 · Physics
Inertia, F = ma, and action-reaction. Written in American English for students, parents, and teachers in the United States.
Open a card to see the answer. These are original practice items for US elementary students — not a state test copy.
Answer: inertia — objects keep their motion unless a net force acts
A book stays at rest on a table.
Answer: F = ma
Net force equals mass times acceleration.
Answer: doubles
a = F/m.
Answer: come in equal-and-opposite pairs
The ground pushes up as you push down.
Answer: the gravitational force on an object
W = mg near Earth.
Answer: kilograms
Force is in newtons.
Answer: velocity is constant (maybe zero)
Balanced forces → no acceleration.
Answer: opposes sliding between surfaces
It is a force, so it can change motion.
Pick the next article in this topic — that is how a magazine issue is meant to be used.