8th Grade Science — Motion and Forces — Inertia Is Measured by Mass

A free 1-page hands-on science activity for 8th Grade (ages 13–14). It practices science, observation, inquiry. Download the PDF with no account and no email.

Free printable inertia is measured by mass science worksheet. Newton's first law is usually read as a rule about what objects do, but it is better read as a definition of inertia. Inertia is measured by mass in kilograms, so a 2,000 kg car resists a change in its motion exactly twice as strongly as a 1,000 kg car under the same net force. Nothing in the law says an object prefers to stay still: it says that with zero net force the acceleration is zero, whatever the velocity already was. Part of the Motion and Forces lesson track. For 8th Grade Science (ages 13–14).