Balanced & Unbalanced Forces

Balanced & Unbalanced Forces

Learning Objective:

• We will identify balanced and unbalanced forces.

Force

• A push or pull on an object.

• Able to change the motion of an object.

• Gravity, friction, and air resistance are three common forces on Earth.

Multiple Select

What are the three most common forces on earth?

• Gravity.

• The Force.

• Friction.

• Air Resistance.

Net Force

• The overall force exerted on an object; measured in Newtons (N).

• If the net force is 0, then a change in motion will not occur.

• If the net force is greater than 0, then a change in motion will occur.

Fill in the Blanks

How do we measure force?

How to calculate net force from a picture or diagram:

• Subtract the forces if the arrows are pointed toward each other or pointed away from each other.

• Add the forces together if the arrows are all pointed the same direction.

Fill in the Blanks

What is the Net Force of this Equation? 5 N + 7 N = 12 N

Balanced Forces

• Equal forces that do not cause a change in an object’s motion (Net Force = 0 Newtons).

• The net force on an object must be calculated in order to determine if it is balanced or unbalanced.

• Forces are balanced when the net force = 0 Newtons.

Multiple Choice

What is this equation? 50 N – 50 N = 0 N

• Balanced.

• Unbalanced.

Balanced Forces

A cell phone resting on the counter.

Balanced Forces

Tying an arm wrestling match.

Balanced Forces

A picture hanging on the wall.

Balanced Forces

Any object with no motion.

Balanced Forces

Any object moving at a constant speed.

Open Ended

Why would an object moving at a constant speed experience balanced forces?

Unbalanced Forces

• Unequal forces that cause a change in an object’s motion.

• Cause a change in speed and/or direction of an object – moves the direction of the greater force.

• Forces are unbalanced when the net force does not equal 0 Newtons.

Multiple Choice

What is this equation? 100 N – 50 N = 50 N

• Balanced.

• Unbalanced.

Unbalanced Forces

A football player tackling a quarterback.

Unbalanced Forces

Pushing a lawnmower across the yard.

Unbalanced Forces

A skydiver falling toward the ground.

Unbalanced Forces

Any object that is speeding up, slowing down, or changing direction (accelerating).

Open Ended

Identify one example of balanced and unbalanced forces in your room.

Open Ended

How can I make this lesson better? (Mentor Sentence: "You can make this lesson etter by...")

Poll

What do you want to learn more about?

• Equations

• Newton's Laws

• Midichlorians

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