Regents Physics Mr. Rockensies

Slides:



Advertisements
Similar presentations
Topics: Forces, Apparent Weight, & Friction
Advertisements

Sliding Friction A force that opposes motion Acts parallel to the
 Friction opposes motion  Friction is dependent on the texture of the surfaces  Friction is dependent on normal force motionfriction.
PHY131H1F - Class 11 Today: Friction, Drag Rolling without slipping
Chapter 5 Assignment: l Problems p 105 – 107 l #’s and Friction a force that opposes motion What do you think friction depends on? It depends.
Newton’s Laws of Motion Problems MC Questions
Aim: How can we calculate static and kinetic friction? A 3.5 kilogram box is being pulled to the right with a force of 15 newtons. The box is moving at.
Friction -A force which opposes motion. There are two types of friction: 1.Static Friction – the force exerted on a stationary object in order to get the.
Do Now: A 40 N chair is pushed across a room with an acceleration of 2 m/s 2. Steven pushes with a force of 15N. What is the force of friction acting on.
What is a force? How does friction affect motion?
Friction is a force that opposes the motion between two surfaces that are in contact  is a force that opposes the motion between two surfaces that are.
Physical Science motion and force. Objectives: –Explain the effects of unbalanced forces on the motion of objects –Compare and contrast static and kinetic.
EVERY-DAY FORCES Force of gravity Normal force Force of friction Universal force of gravity.
FRICTION!.
The force of_________________, F f : 1. F f = A ____________ force that ____________ motion. It is caused by the __________________ ______________________________________.
Aim: How can we define friction? Do Now: A 20 kg object is being pulled across a table at a constant velocity with a force of 58.8 N. Draw a free-body.
Multiple choice Have a go at the two multiple choice questions at the top.
Lecture 9: Forces & Laws of Motion. Questions of Yesterday You must apply a force F to push your physics book across your desk at a constant velocity.
Friction Ffriction = μFNormal.
Friction What is friction?. Answer Me!!! Think of two factors that affect friction.
Friction Physics 11 What’s Stopping You?. Humour again..
Where the Rubber Meets the Road
Physics 151 Week 11 Day 3 Topics: Newton’s 2nd Law and Applications  Applying Newton’s 2nd Law  Apparent Weight  Free Fall  Terminal Velocity  Friction.
FRICTION.
Everyday Forces Chapter 4 – Section 4 St. Augustine Preparatory School October 13, 2016.
 Friction – force that opposes motion  Caused by microscopic irregularities of a surface  The friction force is the force exerted by a surface as an.
Force of Friction Friction acts to oppose motion between two surfaces in contact Friction acts to oppose motion between two surfaces in contact F f F f.
Friction is a type of force between two touching surfaces.
Mu of the Shoe Chapter 2, Activity 6. Friction What is friction? –A–An interaction between a moving object and its environment Produces heat and loss.
Friction and Forces on Inclined Planes. The Normal Force The normal force is the supporting force that acts on the object perpendicular to the surface.
Do Now: A boy pushes a 5Kg box across a floor with a force of 40N. If the force of friction is 10N find the acceleration of the box. (Draw a force diagram)
6 Applications of Newton’s Laws 6-1 Frictional Forces What is friction? To slide one such surface across another requires a force large enough to overcome.
Friction Friction - force between 2 surfaces that oppose motion Two kinds of friction 1) Static Friction - force of friction that must be overcome to move.
Friction. I. Friction A. Background 1. A force that acts opposite the direction of movement 2. Friction slows you down and causes heat.
Chapter 4.1 Notes Resistance (is futile!). ► Newton’s 1st law - Every object in motion stays in motion; Every object at rest stays at rest unless acted.
-A force that opposes motion -Acts parallel to the surfaces in contact.
Warm Up The coefficient of friction is 0.17, and the object is accelerating at 3m/s2 to the right, what is the force in each direction and what is the.
Speed, Velocity, Acceleration Notes. Speed (Distance ÷ time)
Frictional Force A force that opposes motion Acts parallel to the
Sliding Friction A force that opposes motion Acts parallel to the
Newton’s Laws of Motion
Chapter 12 Review a d 13 kg b c A box is accelerated to the right across the smooth surface of a table with an applied force of 40 Newtons. The table surface.
Friction.
Forces Objectives: Definition of a Force Newton’s Three Laws
Gravitation, Friction, and Net Force
Friction is a type of force between two touching surfaces.
The force of Friction Chapter 4.4.
Force and Motion PHYSICS HONORS Lecture Notes
Do Now: A 40 N chair is pushed across a room with an acceleration of 2 m/s2. Steven pushes with a force of 15N. What is the force of friction acting.
2. What happens if the force is increased?
Newton’s Laws Acceleration
Gravitation, Friction, and Net Force
Friction Newton’s 2nd Law with Friction Examples Outline.
Where the Rubber Meets the Road
Aim: How do we explain the force of friction?
The force of_________________, Ff:
Friction.
Force and Motion Physics 2053 Lecture Notes
Contact Friction Forces:
Homework P , 33, 34, 35, 37.
Newton’s 2nd law Problems
Forces and Newton’s Laws of Motion
Friction and Normal Force
Forces and Newton’s Laws of Motion
Aim: How do we explain the force of friction?
Aim: How do we explain the force of friction?
The force of_________________, Ff:
Contact Friction Forces:
Friction.
Static and Kinetic Friction
Presentation transcript:

Regents Physics Mr. Rockensies Friction Regents Physics Mr. Rockensies

These three factors make up the coefficient of friction Friction – a force that opposes motion Occurs whenever there is contact between two surfaces Depends on 4 main factors: The force the surfaces are applying to each other (Normal Force) Materials the surfaces are made of State of motion (static v. kinetic) Presence of a lubricant (wet v. dry) These three factors make up the coefficient of friction

Why does friction occur? When objects are in contact with each other, down at the molecular level, even sooth surfaces have microscopic ridges. Rough surface – more gaps ~ uneven Smooth surface – more even, but still some gaps

A semi truck weighing 2400 N barrels down a highway at 40 m/s. (a) What is the force of friction acting between the tires and the asphalt? (b) How would it change if it were raining? (c) If it were raining and the driver applied the brakes, how far would the truck travel before coming to rest? (d) How long would it take to stop?

A wooden box is at rest on a wood floor. The box is 25 kg. What is the weight of the box? What is the Normal Force acting on the box? What is the force of friction acting on the box? What is the minimum force required to start the box moving? (e) If the box is accelerated at a rate of 5 m/s2, what is the Net force acting on it? (f) What is the Force of friction acting on the box? (g) What is the force applied to actually move the box?

Exploring Friction Using the spring scale and wooden block, determine the force of friction in each of the following scenarios: Block flat on desk vs. block on its side Pulling at a slow speed vs. pulling at a fast speed Pulling across various surfaces Pulling with a weight on top of the block **Make sure to pull at a constant speed**

Record your values on a separate sheet of paper For each scenario, determine whether or not the change affects friction Block flat on desk vs. block on its side Flat - ____ N Side - ____ N Pulling the block either way (does/does not) affect friction