Newton's First Law
Grade 8 · Science · Forces and Motion · Arkansas, USA
Lesson Summary
An object at rest stays at rest, and a moving object keeps moving, unless a force acts on it.
Explanation
Newton's first law is also called the law of inertia. Inertia is the tendency of objects to resist changes in motion. A ball sitting on the ground will not move on its own—something has to push it. A ball rolling across a smooth surface would roll forever if there were no friction or air resistance to slow it down. This law explains why you lurch forward when a car suddenly stops: your body wants to keep moving.
Practice Questions
Q1: Why do passengers lean to one side when a car turns sharply?
Answer: Because of inertia—their bodies want to keep moving in a straight line while the car changes direction.
Q2: A hockey puck slides across the ice and eventually stops. What force stopped it?
Answer: Friction between the puck and the ice surface, even though ice has very little friction.
Q3: What is inertia?
Answer: Inertia is the tendency of an object to resist changes in its state of motion. Objects at rest stay at rest and moving objects keep moving unless acted on by a force.
People Also Ask
What is Newton's First Law in Grade 8 Science?+
Newton's First Law is a lesson in the Forces and Motion chapter of Grade 8 Science. It is part of the Arkansas, USA school curriculum and covers key concepts that students need to understand at this level.
What grade level covers Newton's First Law?+
Newton's First Law is taught in Grade 8 as part of the Science curriculum in Arkansas, USA.
How can I help my child with Forces and Motion in Science?+
Start with the lesson summary and explanation on this page. Practice the questions provided, then use TutorTom for personalized, step-by-step help with Forces and Motion topics.