Are you attending lecture today? 1.Yes 2.No 15 12345.

Slides:



Advertisements
Similar presentations
Friction. Friction - the force needed to drag one object across another. (at a constant velocity) Depends on: How hard the surfaces are held together.
Advertisements

2. What is the coefficient of static friction if it takes 34 N of force to move a box that weighs 67 N? .51.
Aim: More friction Do Now:
Force Test REVIEW.
Circular Motion; Gravitation
Physics 215 – Fall 2014Lecture Welcome back to Physics 215 Today’s agenda: Weight, elevators, and normal forces Static and kinetic friction Tension.
KINETICS of PARTICLES Newton’s 2nd Law & The Equation of Motion
Friction.
Circular Motion Lecturer: Professor Stephen T. Thornton
5.4 highway curves 5.5 Non-uniform circular motion 5.6 Drag Velocity
as the force required before you changed the crate’s orientation.
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 and the Coefficients of Friction
Friction. Static Friction f s - The force on an object that keeps it from slipping f s - The force on an object that keeps it from slipping f s = F push.
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.
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.
Μ must be kidding!. * The Force of Friction depends on: * The surfaces in contact * The amount of the normal force * Whether the object is moving (kinetic)
Forces Mass, Weight, and Friction. Weight Weight: force of gravity on an object - on Earth your weight is a direct measure of the planet’s force pulling.
Physical Science motion and force. Objectives: –Explain the effects of unbalanced forces on the motion of objects –Compare and contrast static and kinetic.
FRICTION!.
Chapter 5 Newton’s Second Law of Motion – Force and Acceleration
Motion Unit Chapter 10.
Common Forces.
Week.  Student will:  Incorporate Force of Friction into calculation  Static Friction  Kinetic Friction.
Force Causes Acceleration
Forces and Free-Body Diagrams
4-4: Everyday Forces Objectives: Explain the difference between mass and weight Find the direction and magnitude of the normal force Describe air resistance.
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.
A highway curve has a radius of km and is unbanked
Friction Ffriction = μFNormal.
Friction What is friction?. Answer Me!!! Think of two factors that affect friction.
Newton’s Second Law of Motion – Force & Acceleration
Period 2 Question 1.
SECTION 5.2 FRICTION Define the friction force.
Unit 3 Forces & Motion. Forces Force- an action applied to an object to change its motion(push or pull) Units of lb, N (equal to kg. m/sec 2 ) If forces.
 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.
A 4.25 kg block of wood has a kinetic coefficient of friction of and a static of between it and the level floor. 0. Calculate the kinetic friction.
Notes: Friction Static friction (F s ) is the force that opposes initial motion between two contacting surfaces. (standing friction) When a force is applied.
Laws of Motion Newton’s First Law. Force changes motion A force is a push or pull, or any action that is able to change motion.
An 7.3-kg object rests on the floor of an elevator which is accelerating downward at a rate of 1.0 m/s 2. What is the magnitude of the force the object.
Period 2 Question 1.
“Straight Forward” Work Problem Steve exerts a steady force of magnitude 210 N on a stalled car as he pushes it a distance of 18 m to the East. The car.
Week.  Student will:  Incorporate Force of Friction into calculation  Static Friction  Kinetic Friction Cornell Notes Needed – Section 5.2.
F f = . F norm Friction “  ” is the coefficient of friction…it represents the types of surfaces that are in contact with each other.
N EWTON ’ S L AWS T EST R EVIEW. I F A MASS FEELS A FORCE, IT ALSO EXPERIENCES AN ACCELERATION. I F THE MASS WERE TO DOUBLE, WHILE KEEPING A CONSTANT.
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.
Chapter 4 Review. Question What is the SI unit of force?
Lesson 6 Objectives Observe the properties of sliding friction. Measure the force of friction on a wooden block pulled across different surfaces. Measure.
Frictional Force A force that opposes motion Acts parallel to the
Forces Objectives: Definition of a Force Newton’s Three Laws
Formative Assessment.
When you ride the Spindletop, you move in a circle at a constant speed
Lec 04: Newton’s Second Law
Friction.
The Normal Force and Friction
The force of Friction Chapter 4.4.
Aim: How do we explain the force of friction?
Friction.
Unit 2 Forces Friction.
Halliday/Resnick/Walker Fundamentals of Physics 8th edition
Friction and Normal Force
5-2 Uniform Circular Motion—Kinematics
Aim: How do we explain the force of friction?
Force of Friction.
Warm up What do you think causes friction? What are some high friction surfaces? Some low friction surfaces?
Bell Work: Friction Details
Friction and the Coefficients of Friction
Centripetal Force and Banked Curves Chapter 5 Lesson 2
Friction Ff =  . Fnorm “” is the coefficient of friction…it represents the types of surfaces that are in contact with each other.
Presentation transcript:

Are you attending lecture today? 1.Yes 2.No

A car goes forward along a level road at constant velocity. The total force acting on the tires is greater than the normal force times the coefficient of static friction. 2.equal to the normal force times the coefficient of static friction. 3.the normal force times the coefficient of kinetic friction. 4.zero.

A dancer stands on her toes. What is the pressure exerted by the floor over the area of contact if the dancer is stationary? Dancer weight50.0 kg Contact area26.0 cm x 105 Pa x 105 Pa

Two small cylindrical plastic containers with flat bottoms are placed on a turntable that has a smooth flat surface. Canister A is empty; canister B contains lead shot. Each canister is the same distance r from the center. The coefficient of static friction between the canisters and the turntable is. When the speed of the turntable is gradually increased, a. only the lighter container slides outward off the turntable; the heavier one stays on. b. only the heavier container slides outward off the turntable; the lighter one stays on. c. both containers slide off the turntable at the same turntable speed. d. the lighter container slides inward. e. the heavier container slides inward. :20

Evaluate the integral:. 1. e x – 9 ln (9 + e x ) + C 2. e x + 9 ln (9 + e x ) + C 3.9e x – 9 ln (9 + e -x ) + C 4.9e x – ln (9 + e -x ) + C Answer Now