Energy Transfer….. Examples of lots of Kinetic Energy.

Slides:

Advertisements

Similar presentations

P2 Additional Physics.

Advertisements

CBA #1 Review Graphing Motion 1-D Kinematics Projectile Motion Circular Motion Gravity Graphing Motion 1-D Kinematics Projectile Motion Circular.

Time (s)012 Mass of car & bucket (kg) Mass of falling bucket (kg) Force of falling bucket (F = m x a (earth) ) (N) Acceleration of the system ( F = m.

Sect. 8-3: Mechanical Energy & It’s Conservation.

J E O P A R D Y ! Motion Identify the rate EnergyUnitAcceleration Allah e5alee el calculator Col VII Col VIII

The work-energy theorem. Objectives Investigate quantities using the work-energy theorem in various situations. Calculate quantities using the work-energy.

Do Now: 1. Draw a free body diagram (all the forces) acting on a water skier being pulled by a boat. 2. What is the net force acting on this object?

a) The kinetic energy of the car. b) The distance it takes to stop.

Kinetic energy. Equations The kinetic energy of a moving object is one half of the product of its mass multiplied by the square of its velocity. or.

Phy100: More on Energy conservation Mechanical energy (review); Goals: Work done by external forces; Understand conservation law for isolated systems.

Dr. Jie Zou PHY 1151G Department of Physics1 Chapter 7 Work and Kinetic Energy (Continued)

Mechanical Work: More Practice. Gravitational Potential Energy: More Practice.

Dr. Jie Zou PHY 1151G Department of Physics1 Chapter 7 Work and Kinetic Energy (Continued)

NEWTON’S SECOND LAW OF MOTION Law of Acceleration.

CBA #1 Review Graphing Motion 1-D Kinematics

Newton’s 2 nd Law. Force on Object Objects acted on by a net unbalanced force will accelerate in the direction of the force This means they will speed.

Kinetic Energy A moving object has energy because of its motion. This energy is called kinetic energy.

Kinetic energy Derivation of kinetic energy. Kinetic Energy 2 starting equations F = m x a (Newton’s 2 nd law) W = Force x distance.

Sect. 7-4: Kinetic Energy; Work-Energy Principle.

Forces and Motion 4.05 Determine factors that affect motion including: Force Friction. Inertia. Momentum.

REVISION What two parts make up the stopping distance of a vehicle?

Newton’s 1 st Law Inertia. Force Anything capable of changing an object’s state of motion Any push or pull Causes object to speed up, slow down, or change.

Forces Chapter 6.1. What You Already Learned Velocity is the ratio of the change in position of an object over a period of time. Acceleration describes.

100 Newton's 1 st Law Newton's 2 nd Law Newton's 3 rd Law Terms & Units

Power and Efficiency And a review of the work-energy theorem.

Friction Ffriction = μFNormal.

Lecture 10: Work & Energy.

Physics the study of the relationship between matter and energy

Physics Review for the GHSGT. Speed Measure of how quickly an object gets from one place to another.

P3 Physics Forces for transport. Speed  Miles per hour  Kilometres per hour  Metres per second  Centimetres per second  Kilometres per second  So.

Coefficient of Friction The force of friction is directly proportional to the normal force. When we increase the mass or acceleration of an object we also.

Impulse, Momentum and Collisions. momentum = mass x velocity p = mv units: kgm/s or Ns.

Formulas. Work Units – joules (J) Power Units – watts (w)

Kinetic Energy and Work. Energy Loosely defined as the ability to do work There are many types of energy, but the total energy of a system always remains.

K INETIC E NERGY AND W ORK. E NERGY Loosely defined as the ability to do work There are many types of energy, but the total energy of a system always.

Physics 1D03 - Lecture 19 Kinetic Energy. Physics 1D03 - Lecture 19 Then the Work-Energy Theorem says: The total work done by all external forces acting.

Forces Chapter 6.1. What You Already Learned Velocity is the ratio of the change in position of an object over a period of time. Acceleration describes.

4.1b Notes – Calculations using Net force and Newton’s 2 nd Law.

The Work-Energy Theorem Derivation: v f 2 =v i 2 +2ad Kinematics Equation mv f 2 =mv i 2 +2madDynamics equation (1/2)[mv f 2 =mv i 2+2mad] mad= ½ mv f.

Objectives: The student will be able to: 1. Define each type of mechanical energy and give examples of types of energy that are not mechanical. 2. State.

Chapter 6 and 7. momentum = mass x velocity p = mv units: kgm/s or Ns.

Forces Year 11 GCSE Physics Module 11. Starter  What is the unit of measurement of a force?  How fast is a cat travelling who covers 30m in 5s?  What.

1 Conservation of Energy “with non-conservative forces” Some Key Terms Internal force: any force exerted on an object in the system due to another object.

1 PHYSICS TOPICS Index © DIRECT-SCIENCE : WORK-(KINETIC) ENERGY THEOREM With every click information will appear on the screen.

Newton’s Law of Universal Gravitation

Forces Chapter 6.1. What You Already Learned Velocity is the ratio of the change in position of an object over a period of time. Acceleration describes.

Work and Kinetic Energy 1- Outline what is meant by Kinetic Energy. 2 - List different forms of energy and describe examples of the transformation of.

P2a Forces and Their Effects Distance vs Time Graphs Velocity vs Time Graphs *Area under vel time graphs gives the distance travelled *The slope gives.

Vocabulary Work Problems Potential Energy Problems Kinetic Energy Problems Extra Questions

Work W-E Theorem Pt. 1 1 Newton’s Second Law in Terms of Work Conservation of Kinetic Energy Work-Energy Theorem Work-Energy Diagram.

“Law of Acceleration” Forces can be BALANCED or UNBALANCED Balanced forces are equal in size (magnitude) and opposite in direction UNbalanced.

Newton’s Laws We have already looked at Newton’s laws. Now we are going to look at them in more depth. You may have to revise this work if you can not.

P2 Additional Physics.

Vehicular Stopping Distance

Test Review Dynamics.

Work and Energy.

Newton’s Second Law of Motion

ENERGY EQUATIONS By the end of this presentation you should be able to: Calculate kinetic energy, work and power.

P2 Higher Revision - The harder bits.

a) find the acceleration

Which one would be easier to accelerate by pushing?

Notes 2.2: Newton’s 2nd Law of Motion

Force and Motion Jeopardy Review

Kinetic Energy.

KINETIC ENERGY: ENERGY OF MOTION

Newton’s Laws.

Lesson 18 Newton’s second Law

Force and Motion Jeopardy Review

Presentation transcript:

Energy Transfer….

Examples of lots of Kinetic Energy

What about this one….

So what does K depend on? Kinetic Energy depends not only on the speed, but also the mass of the object. K = ½ mv 2 Increasing velocity has a greater effect than increasing mass

Proportional Reasoning What would happen to the kinetic energy of an object if I…. Doubled the mass? Quadrupled the mass? Cut the mass by 1/3?

Proportional Reasoning What would happen to the kinetic energy of an object if I…. Doubled the velocity? Quadrupled the velocity? Cut the velocity by 1/3? 4x

Calculations Usain Bolt has a mass of 94 kg and can reach a speed of 12.2 m/s. Calculate his K. At 31 m/s, the cheetah has 28,830 J of kinetic energy. Calculate his mass. T-Rex has a mass of 6,000 kg and has 192,000 J of kinetic energy. Calculate his velocity.

Show car video

Show sliding car

Now it’s time for calculations… Here is a graph of v vs. t…. What is the car’s initial velocity? What is the car’s final velocity? Mass of the prius is roughly 2,000 kg Calculate the change in kinetic energy…

Draw Free Body Diagram for the car after applying the brakes… What direction is the car moving? What direction is friction? What does this tell you about the work being done on the car?

Calculating Work W = F x d Force – Only force doing work is friction, and Newton’s 2 nd Law states that F = ma. W = (ma) x d We know the mass of the prius, but what about its acceleration?

Looking back…. How did we find acceleration from a v vs. t graph?

Calculating Work… We had the equation, W = (ma) x d We now know m and a… What about the distance travelled? How can we get it from the v vs. t graph? Area….but that isn’t a pretty shape.

x vs. t graph is WAY easier

Calculating Work… We’re still doing this?!?

Calculating Work… W = (ma) x d W = 2000 kg x m/s/s x m W = -32, J

But wait… We said the change in kinetic energy was -32,670 J And the work done by friction was equal to -32,707 J. That’s because…. W = ΔK Work-Energy Theorem