MOTION & ITS APPLICATIONS Everyday Forces (P )

Slides:



Advertisements
Similar presentations
Draw It!!.
Advertisements

Chapter 4.1: Changes in Motion
Force Force is a push or pull on an object The object is called the System Force on a system in motion causes change in velocity = acceleration Force is.
Forces and Free Body Diagrams 11/6/13. Bellwork What book did Newton write in 1687? What book did Newton write in 1687? The Principia (Mathematical Principles.
Forces and Free Body Diagrams 12/3/14. Contact Forces Applied Force Applied Force Surface Force Surface Force Friction Force Friction Force Air Resistance.
Everyday forces and free body diagrams
FORCES. A force is an influence on a system or object which, acting alone, will cause the motion of the system or object to change. If a system or object.
Projectile Motion A projectile is an object on which the only force acting is ______ and the direction of this force is always _____. (In real life, a.
Scalar Quantities  Measurements that are fully described by a magnitude (or numerical value) alone.  Examples: Mass- 70kg Speed- 45mph Distance- 100m.
Forces and Free Body Diagrams
Free Body Diagrams and Vector Diagrams.  Recap from ICT Package  Free Body Diagrams  Types of Component Forces  Vector Diagrams.
An Introduction to Forces: Student Learning Goal The student will analyse, in quantitative terms, the forces acting on an object, and use free-body diagrams.
Forces and Free-Body Diagrams
Forces and Free Body Diagrams. Common Forces Gravity- attractive force between two objects that have mass. AKA Weight To calculate Weight: –Force of Gravity.
An Introduction to Forces SPH4C. A Definition A force is a push or a pull. It is a vector quantity and is symbolized by: In the SI system, force is measured.
Unit Two: Dynamics Section 1: Forces. What Do I Already Know? Take 10 minutes to discuss with the person next to you. You can use your textbook and/or.
Forces An Introduction.
FORCES AND FREE BODY DIAGRAMS  011/mar/04/brian-cox-forces-nature-video
PHYSICS 11 SOLVING F=MA PROBLEMS USING FREE BODY DIAGRAMS.
LESSON 13 FEBRUARY 4 TH, 2011 Forces and Free body Diagrams.
Free Body Diagrams and Vector Diagrams.  Recap from ICT Package  Free Body Diagrams  Types of Component Forces.
I. Newton’s Laws II. Forces III. Free-Body Diagrams Chapter 4: Newton’s Laws and Forces.
Forces. Log into my website, click the Introduction to Forces Notes On a note card, define the following terms: Force Newton Unbalanced force Contact.
Forces Chapter 4.
Forces.
Free body diagrams.
Unit Two: Dynamics Section 1: Forces.
Forces & Laws of Motion Ch 4 Physics.
Force.
FORCES AND FREE BODY DIAGRAMS
Free Body Diagrams & Net Force
Forces An Introduction.
Forces and Free Body Diagram Notes
Bell Ringer Name three types of forces and what they do.
Review What do we already know?
Let’s begin with some skydiving movies.
FORCES.
An Introduction to Forces
Newton’s First Law Pre-AP Physics.
FORCES AND FREE BODY DIAGRAMS
Force and Motion.
FORCES.
Forces and Free Body Diagrams
Review: Newton’s 1st Law
Forces and the Laws of Motion
Fold in half longways 7 cuts to make 8 flaps
Do Now Susan’s displacement is 12 m left. First she walked 20 m left. How far right did she walk? Dan’s resultant velocity in a boat is 8 m/s right.
Newton’s Laws of Motion Chapters 2,3,6,7
Forces and Free Body Diagrams
FORCE – CAUSES CHANGES IN MOTION
Forces and Newton’s Laws of Motion
DO NOW QUESTION What forces are present on the monkey?
Free Body Diagrams.
Forces and Free body Diagrams
Drawing Free Body Diagrams
Forces and the Laws of Motion
Step 1: Get Organized Draw a picture.
Forces and Free Body Diagram Notes
Forces and Motion Review Macroscopic Forces
Warm-up What forces were acting on your rocket when it was moving up into the air? What forces were acting on your rocket when it was coming back down.
Forces and Motion FINAL JEOPARDY Go To Score Card Forces Gravity
Forces and Motion FINAL JEOPARDY Go To Score Card Forces Gravity
Free Body Diagrams and Types of Forces
Forces in Equilibrium Name: _______________
Newton’s 3rd Law and Free Body Diagrams
Forces and Motion FINAL JEOPARDY Go To Score Card Forces Gravity
Free body diagrams.
Forces and Motion FINAL JEOPARDY Go To Score Card Forces Gravity
Forces Pg
Forces and Motion FINAL JEOPARDY Go To Score Card Forces Gravity
Presentation transcript:

MOTION & ITS APPLICATIONS Everyday Forces (P .27-31) SPH4C COLLEGE PHYSICS MOTION & ITS APPLICATIONS Everyday Forces (P .27-31)

Forces We Experience Daily We experience several types of forces daily. Imagine two children playing outside with a wagon. One child pulls forward on a rope tied to the front, while the other pushes on the wagon from behind. What forces act on the wagon?

Forces We Experience Daily In order to analyze the different types of forces acting in this situation two types of force diagrams – system diagrams and free-body diagrams – are useful. A system diagram (like the one below) is a sketch of all the objects involved in a situation.

Forces We Experience Daily A free-body diagram (FBD) is a simple drawing representing the object being analyzed and all the forces acting on it. The object is typically shown as a rectangle or large dot with the forces drawn as arrows originating from the object and pointing away from the center. Each force is labelled with the symbol F and an appropriate subscript that indicates the force.

Forces We Experience Daily– Tension Force (FT) Another force is the tension force (often called tension). Tension (FT) is a pulling force exerted on an object by a rope or a string. In our example, the child at the front of the wagon pulls on the rope, causing tension in the rope. The rope exerts tension on the wagon, pulling it forward.

Forces We Experience Daily – Normal Force (FN) Whenever an object is in contact with a surface, the surface can exert two different forces on the object. One is called the normal force. The normal force (FN) is a perpendicular force exerted on an object by the surface with which it is in contact. In our example, the ground is pushing up on the wagon.

Forces We Experience Daily– Friction Force (Ff) The other force exerted by a surface on an object is friction. Friction (Ff) is a force that resists the motion or attempted motion of an object and always acts parallel to the surface. In our example, if the wagon is moving right, then friction acts toward the left. Even if the wagon was at rest with the children pushing and pulling on it, friction would still be present.

Forces We Experience Daily– DYK? NOTE! The forces described thus far require one object to be in contact with another. For this reason, they are called contact forces. Some forces, however, do not require contact. These action-at-a-distance forces are called non-contact forces.

Forces We Experience Daily– Force of Gravity (Fg) The force of gravity (Fg), also called the gravitational force, is the force of attraction that exists between any two objects. The direction of this force is toward Earth’s centre. In our example, the force of gravity pulls down on the wagon.

Forces We Experience Daily– Force of Gravity (Fg) NOTE! The force of gravity (Fg ) is an example of a non-contact force (i.e. it is a force that acts at a distance). To calculate the force of gravity acting on an object, you can use the equation, where m is the mass of the object (kg), and g is the acceleration due to gravity (m/s2). We will study this topic in more detail later!

Forces We Experience Daily EVERYDAY FORCES Force of Gravity (Fg)  force of attraction between Earth and object Normal Force (FN) force ü to surface upon which object rests Friction Force (Ff) force that opposes (attempted) motion of object Applied Force (Fa)  force exerted on object Tension Force (FT)  force exerted by string or rope on object NOTE! The force of gravity is a non-contact force (i.e. it does not require contact in order to be experienced). Fg=mg

External Forces & Internal Forces In this course, we will usually be concerned with external forces. External forces are those that are caused by one object pushing or pulling on another. An internal force occurs when an object exerts a force on itself. For example, when skater 1 pushes on skater 2, the force on skater 2 is external. If skater 1 pulls forward on her own arms, then it is an internal force.

External Forces & Internal Forces occurs when one object pushes/pulls on another object INTERNAL FORCE occurs when an object exerts a force on itself

Free-Body Diagrams NOTE! In order to study the effects of forces acting on any object the use of a free- body diagram (FBD) is necessary. Recall that a FBD is a simple drawing that shows the object being analyzed and all the forces acting on it. It does not include forces that the object itself exerts

Free-Body Diagrams FREE-BODY DIAGRAM (FBD) drawing that represents the object being analyzed and all the external forces acting on it it does not include forces that the object itself exerts

Forces We Experience Daily & FBDs PRACTICE Draw a FBD for the object in bold. (a) A cup is sitting at rest on a table.

Forces We Experience Daily & FBDs PRACTICE Draw a FBD for the object in bold. (b) A large trunk is pulled by a rope tied to the right side. The floor is rough and the trunk does not move.

Forces We Experience Daily & FBDs PRACTICE Draw a FBD for the object in bold. (c) A baseball player is sliding to the left across the ground.

Forces We Experience Daily & FBDs PRACTICE Draw a FBD for the object in bold. (d) A desk is pushed to the left across the floor.

Forces We Experience Daily & FBDs PRACTICE 2. For each situation described below, draw a FBD for object in bold. Be careful when deciding what forces are acting on each object. If you cannot think of a cause for the force, the force may not even exist. (a) Your textbook resting on your desk.

Forces We Experience Daily & FBDs PRACTICE 2. For each situation described below, draw a FBD for object in bold. Be careful when deciding what forces are acting on each object. If you cannot think of a cause for the force, the force may not even exist. (c) A fully loaded dog sled, moving slowly along a flat but rough & snowy trail, is being pushed horizontally by the sled owner while being pulled horizontally by dogs attached to it by rope.

Forces We Experience Daily & FBDs PRACTICE 2. For each situation described below, draw a FBD for object in bold. Be careful when deciding what forces are acting on each object. If you cannot think of a cause for the force, the force may not even exist. (b) A tennis ball falling through the air from the server’s hand. Neglect air resistance.

Forces We Experience Daily & FBDs PRACTICE 2. For each situation described below, draw a FBD for object in bold. Be careful when deciding what forces are acting on each object. If you cannot think of a cause for the force, the force may not even exist. (d) A wagon with a small child sitting in it is being pulled by a rope up a steep bumpy hill with the rope parallel to the hillside.

Check Your Learning TEXTBOOK P .31 Q.1-5