“ A force to be reckoned with” FORCES “ A force to be reckoned with”

EQ: How do balanced and unbalanced forces affect an object? S8P5.a – Recognize that every object exerts gravitational force on every other object and that the force exerted depends on how much mass the objects have and how far apart they are. S8P3.b – Demonstrate the effect of balanced and unbalanced forces on an object in terms of gravity, inertia, and friction.

AS YOU ENTER… Look around the room and think about the objects you see in terms of FORCE. HINT: A force is always exerted by one object to another object. Answer the following: Where do you see a force happening in this room right now? Which object is exerting the forces, and which is receiving it?

Carousel Brainstorming Each group should stand in front of one question station Using your marker, your group should respond to the question on the paper for 2-3 minutes. When time is called rotate clockwise to the next station and repeat until you have visited all stations. ACTIVATOR/SUMMARIZER:Generate X number of questions for your topic of study and write each question on a separate piece of poster board or chart paper. Divide your students into groups of 5 or less. For example, in a classroom of 30 students, you would divide your class into 6 groups of five that will rotate around the room during this activity. It is advisable to use a different color for tracking each group.

Definition of FORCE A push or pull EX: - Using your fingers to pull open books - Pushing buttons on a computer keyboard

FORCE All forces have both size and direction. The unit of force is the Newton (N). Name two other concepts we are currently studying that have both size and direction: Velocity Acceleration

DEFINITION OF NET FORCE The combination all of the forces acting on an object.

Determining the Net Force of an object When forces act in the same direction, you add the forces to determine the net force. The net force will be in the same direction as the individual forces.

Determining the Net Force of an object When two forces act in opposite directions, you subtract the smaller force from the larger force to determine the net force. The net force will be in the same direction as the larger force.

Balanced Forces When the sum of the forces acting on any object equal to zero, the forces are said to be balanced. Forces are balanced when they are equal in size and opposite in direction. THERE IS NO CHANGE IN VELOCITY WHEN THE FORCES ARE BALANCED! Constant speed exists.

Examples of Balanced Forces A light hanging from the ceiling A Bird’s nest in a tree A hat resting on your head A resting elevator

How is this picture an Example of Balanced Forces?

Unbalanced Forces Unbalanced forces occur when the sum of the forces acting on any object is not equal to zero. Unbalanced forces produce a change in motion, such as a change in speed or a change in direction. Unbalanced forces are necessary to cause a nonmoving object to start moving.

Examples of Unbalanced Forces Soccer players kicking a soccer ball. -Competing in an arm wrestling competition against a world famous body builder

Unbalanced Forces Unbalanced forces occur when the sum of the forces acting on any object is not equal to zero. Unbalanced forces produce a change in motion, such as a change in speed or a change in direction. Unbalanced forces are necessary to cause a nonmoving object to start moving.

THE BIG IDEA Unbalanced forces cause changes in motion that can be predicted and described.

Forces, Mass & Acceleration An object accelerates when a net force acts upon it. The relationship between force, mass, and acceleration can be summarized by the following formula: F = ma Acceleration depends on both the net force applied and the mass of the object.

Example Problem #1  

Example Problem #1  

Example Problem #2  

Example Problem #2  

Write an Example of a Balanced Force. Draw a T chart on the right side of your paper and complete the instructions in each box. How much force is needed to make a 150 kg object accelerate at a rate of 2 m/s2? alsd Write an Example of a Balanced Force. Where do you see a force happening in this room right now? Which object is exerting the forces, and which is receiving it? Draw a Visual Representation of Unbalanced Force After students get their respective corner, have a different activity at each. These could be different types of activities or each corner could be a level of difficulty: one corner easier problems, another not so easy, a challenging corner, etc.