Explain how Newton's First Law relates to the concept of inertia. Provide an example from everyday life.

Newton's First Law states that an object in motion stays in motion and an object at rest stays at rest unless acted upon by a force. Inertia is the tendency of an object to resist changes in its state of motion. Therefore, Newton's First Law is essentially a description of inertia. Example: A soccer ball will not move until a player kicks it (applying a force), and once kicked, it would keep going forever unless friction and air resistance slow it down.

A box is pushed across a floor with a force of 10 N. The force of friction opposing the motion is 2 N. If the box has a mass of 4 kg, what is the acceleration of the box? Show your work.

First, calculate the net force: Fnet = Applied Force - Friction = 10 N - 2 N = 8 N. Then, use Newton's Second Law (Fnet = ma) to find the acceleration: a = Fnet / m = 8 N / 4 kg = 2 m/s². The acceleration of the box is 2 m/s².

A book rests on a table. According to Newton's Third Law, what is the reaction force to the force of gravity acting on the book?

The book exerting an upward gravitational force on the Earth.

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Newton's Laws of Motion

Name: Newton's Laws of Motion
Author: Insta~Lesson

8th GradeScience30 min

aligned to Ngss Ms-ps3-1, Ms-ps2-2, Ms-ps2-1

Learning Objective

I can explain how Newton's laws of motion describe the relationship between forces and motion.

Lesson Flow

Watch Video

12 min

Newton's Laws: Crash Course Physics #5

CrashCourse

Practice

10 min

3 questions • Multiple choice & Short answer

Exit Ticket

5 min

“Explain how Newton's first law relates to the concept of inertia, using the example of a bowling ball versus a beach ball.”

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