Newton's First Law of Motion

Newton's First Law of Motion...

Today, you will work with your group to complete this exploration. And thank you Chris Kesler @ keslerscience.com

Read It! Station Instructions

Each member of the group will read the passage and answer the questions from the task cards on the lab sheet in the Read It! section.

It is important to remember that the answers will come directly from the reading passage.   

The Law of Inertia...

Sir Isaac Newton was an English scientist famous for describing physics – the science of movement. Specifically, he formulated three laws of motion. This does not mean he invented the concepts of motion and gravity or the Earth’s downward pull. Rather, he studied forces, pushes, or pulls on objects that cause objects to change their speed and/or direction. Newton’s laws help explain an object’s motion after something exerts a force on it. Sometimes objects even resist forces that have been exerted upon them, which affects their motion as well.

Newton’s 1st Law states, “An object in motion continues in motion with the same speed and in the same direction unless acted upon by an unbalanced force.” The same is true of an object at rest – an object stays at rest until it is acted upon by an unbalanced force. Newton’s 1st Law is also called the Law of Inertia (pronounced inn-urr-shuh). All objects possess something called inertia, or their tendency to keep doing what they’re already doing and resist changes in motion. Without an unbalanced force, an object will maintain its state of motion or rest.

Did you know you have inertia when you ride in a car? A car’s passengers tend to experience the same motion as the vehicle; they accelerate as the car speeds up and decelerate as the car slows down. This is why it is so important to wear a seatbelt! 

Imagine your car is moving forward at highway speeds, and then it collides with another vehicle. The other vehicle exerts an unbalanced force on yours, which causes your car to decelerate to rest abruptly. If you are belted in, your body will decelerate with the vehicle. However, imagine you are not wearing a seatbelt. What do you think happens? With nothing keeping you attached to the vehicle, you will not share the vehicle’s change in motion. Instead, your body’s inertia will cause it to continue moving forward at the same rate of motion and in the same direction, which could cause harm.

It’s a good thing we can study forces and motion in the world around us. Newton’s Laws help us understand how objects move, which helps us enjoy things like sports and roller coasters. But they also help keep us safe! 

Multiple Choice

What would be another good title for this passage?

• A.The Story of Isaac Newton

• A.Newton’s 3 Laws

• A.How Seatbelts Work

• A.An Explanation of Newton’s 1st Law of Motion and Inertia

Multiple Choice

Which of the following objects has the most inertia?

• a pen

• a bowling ball

• a ping pong ball

• a car

Multiple Choice

According to the article, what is one benefit of a seatbelt?

• It decreases the passenger’s inertia.

• It allows you to share the same motion as the vehicle.

• It makes you fly out of the car when stopping.

• It prevents gravity from affecting the passenger.

Watch It! Station Instructions

Watch the video and be ready to answer the questions on the next slides.

Multiple Choice

What is inertia?

• Inertia is an object’s resistance to change in motion.

• Inertia is anything that makes a moving object slow down or stop.

Multiple Choice

What is friction?

• Friction is anything that makes a moving object keep going.

• Friction is anything that makes a moving object slow down or stop.

Multiple Choice

What will happen to an object if it is put into motion in space?

• It will stop eventually due to friction.

• It will continue to move until it is acted on by an unbalanced force.

• It will speed up over time.

• It will slow down over time.

Assess It! Station Instructions

Each member will answer the questions from the task cards...

Multiple Choice

Which force opposes motion between two surfaces in direct contact?

• inertia

• mass

• friction

• acceleration

Multiple Choice

Newton’s 1st Law applies to…

• only moving objects

• only nonmoving objects

• both moving and nonmoving objects

• no objects, except those in space

Multiple Choice

You push a sofa, but you can’t get it to move by yourself. Why?

• You have more inertia than the sofa.

• There is no inertia because the sofa is not moving.

• Your force is stronger than the friction between the sofa and the floor.

• The sofa’s inertia is greater than your applied force.