Ch 8 Energy Notes ENERGY – 5.2 PPT.

Slides:



Advertisements
Similar presentations
Unit 5-2: Energy. Mechanical Energy When mechanical work is done, mechanical energy is put into or taken out of an object. Mechanical energy is a measurement.
Advertisements

Energy Chapter 5 Section 2. What is Energy? Energy – A scalar quantity that is often understood as the ability for a physical system to produce changes.
Energy.
THE NATURE OF ENERGY IPC Notes. ENERGY Energy is involved in every change that occurs Energy can be found in many different forms ex) thermal, electrical,
Energy Conversion  Energy can be changed from one form to another. Changes in the form of energy are called energy conversions.
Kinetic Energy Kinetic energy is energy of motion. Kinetic energy is a scalar quantity. KE = ½ mv 2 kinetic energy = ½ mass x (speed) 2 Units for KE are.
Kinetic and Potential Energy
Kinetic and Potential Energy Notes Chapter 5-2. Mechanical Kinetic Energy Amount of energy an object has based on motion Depends on the mass of the object.
Energy: Forms and Changes. Nature of Energy EEnergy is all around you! You can hear energy as sound. You can see energy as light. And you can feel it.
Energy. Nature of Energy EEnergy is all around you! You can hear energy as sound. You can see energy as light. And you can feel it as wind.
Energy: Forms and Changes. Nature of Energy EEnergy is all around you! You can hear energy as sound. You can see energy as light. And you can feel it.
ENERGY Part I.
Chapter 4. The nature of energy Energy: The ability to do work or cause change All energy involves either motion or position Where are we using energy.
Energy & Conservation of Energy Honors Physical Science.
Energy: Forms and Changes. EEnergy is all around you! YYou can hear energy as sound. YYou can see energy as light. AAnd you can feel it as wind.
Energy & Conservation of Energy Honors Physical Science.
Physics Chapter 11 Energy.
What happens to the gravitation force on an object as it gets closer to another object? Agenda for Monday Nov 10 th 1.Quiz 2.Energy Notes.
TAKE CORNELL NOTES ON A LOOSE SHEET OF NOTEBOOK PAPER. TURN THIS IN ON THURSDAY, 2/20/14.
Mechanical Energy Ch. 4. Energy Is the ability to do work. Energy = work Units = Joules (J) James Prescott Joule.
Chapter 5 Section 1  Every change that occurs requires energy.  Energy is the ability to do work.  All moving objects have energy  You can tell an.
Energy Chapter 5 Section 2.
Potential and Kinetic Energy. What is Energy  Energy –is the ability to do WORK!!!  Two types of energy –Potential Energy –Kinetic Energy.
Work and Energy Energy Chapter 5: Section 2. Learning Targets Identify several forms of energy Calculate kinetic energy for an object Distinguish between.
Work has a specific definition in physics. Work is done anytime a force is applied through a distance.
Nature of Energy Energy is all around! You use energy when you: Sound
Energy: Forms and Changes. States of Energy  The most common energy conversion is the conversion between potential and kinetic energy.  All forms of.
DAILY QUESTION January 28, What is potential energy?
Physics Section 5.2 Define and apply forms of mechanical energy. Energy is the ability to do work. Kinetic energy is the energy of an object due its motion.
“Positive” and “Negative” Activity Physics. The Many Forms of Energy Section 11.1 Physics.
Work and Energy Energy. Kinetic Energy Kinetic energy – energy of an object due to its motion Kinetic energy depends on speed and mass Kinetic energy.
Work Work Work –Work is done on an object when a force is applied and it moves in a direction that is parallel to the force acting on it.
Forms and Conservation ENERGY. Nature of Energy Energy is all around you! _______________________. _______________________. ________________________.
Energy: Forms and Changes. Nature of Energy EEnergy is all around you! You can hear energy as sound. You can see energy as light. And you can feel it.
ENERGY P.E. and K.E. Nature of Energy Energy is all around you! You can hear energy as sound. You can see energy as light. And you can feel it as wind.
Energy and Work. Work… Work = Force // x Displacement W = F // x d ** Remember that displacement is the distance AND direction that something moves. It.
Energy: Forms and Changes. Nature of Energy EEnergy is all around you! You can hear energy as sound. You can see energy as light. And you can feel it.
Mechanical Energy -Potential & Kinetic Energy
Rube Goldberg page turner
Energy Section 14.3 Energy.
Kinetic and Potential Energy
Energy: Forms and Changes
Types and Forms of Energy
Energy.
Energy Ch. 4-1.
Chapter 5.3 Review.
Energy. Energy Energy (def.) the ability to do work. Unit is Joules. Work and energy are interrelated. Work must be done on an object to get it to.
Warm Up In your own words, what is energy? You don’t have to be right, just write down what you think energy is. How do you think energy different from.
Potential and Kinetic Energy
KE and PE Practice Quiz Solutions.
Energy Chapter 4.
Potential and Kinetic Energy
Think Pair Share As the girl swings back and forth, describe her potential energy and kinetic energy at A, B, and C. A C B.
Physical Science Energy.
BELLWORK 2/01/17 From the work-kinetic energy theorem, we see that the speed of an object ______ if the net work done on it positive, because the final.
Energy.
Energy – the ability to do work W = Fd = m a d Vf 2 = Vi2 + 2aDx Vf 2 - Vi2 = + 2aDx Vf.
Energy: Forms and Changes
Energy Chapter 4.
Work-Energy Theorem Energy is the ability to do work.
Energy.
Work and Energy Energy.
Mechanical Energy, Me (Units of joules (J))
Energy: Forms and Changes
GEORGIA S8P2 Students will be familiar with the forms and transformations of energy Explain the relationship between potential and kinetic energy.
Unit 5 ENERGY.
Energy.
Potential & Kinetic energy
Ch 4 Energy Kinetic Energy (KE) – the energy a moving object has because of its motion; depends on mass and speed of object KE = mv2/2 Joule – SI unit.
Presentation transcript:

Ch 8 Energy Notes ENERGY – 5.2 PPT

Kinetic Energy If an object is moving, it has energy. Ch 8 Energy Notes Kinetic Energy If an object is moving, it has energy. This energy is called kinetic energy - the energy of motion.

Kinetic Energy An object’s kinetic energy depends on: Ch 8 Energy Notes Kinetic Energy An object’s kinetic energy depends on: the object’s mass. Kinetic energy is directly proportional to mass. the object’s speed. Kinetic energy is directly proportional to the square of the object’s speed.

Ch 8 Energy Notes Kinetic Energy In symbols: 1 KE = mv2 2

Kinetic Energy Kinetic energy is a scalar quantity. Ch 8 Energy Notes Kinetic Energy Kinetic energy is a scalar quantity. Common units of kinetic energy: Joules An object with mass of 1 kg, moving at 1 m/s, has a kinetic energy of 0.5 Joule.

Example #1 Determine the kinetic energy of a 625-kg roller coaster car that is moving with a speed of 18.3 m/s. Given: mass = 625 kg V = 18.3 m/s Formula: KE = ½ mass x v2

Answer 1.05 x 105 J

Example #2 If the roller coaster car in the above problem were moving with twice the speed, then what would be its new kinetic energy? What is the relationship between KE and velocity?

ANSWER 4.20 x 105 J KE =the square of an object’s velocity. The speed doubled, so the amount of KE increased by 4. If the speed triples, then KE will increase by _____.

Work-Energy Theorem What is the relationship between work and energy? The amount of work done is essentially the change in kinetic energy.

Ch 8 Energy Notes Work When the kinetic energy of an object changes, work has been done on the object. Units of work: Joules Work is a scalar quantity.

Work-Energy Theorem Wnet = Δ KE Wnet = KEf – KEi Wnet = 1/2mv2f – 1/2mv2i From this theorem, we see that the speed of an object increases if the net work done is positive, because the final KE is greater than the initial KE The speed of an object decreases if the net work is negative, because the final KE is less than the initial KE.

Potential Energy Potential Energy is stored energy. Stored chemically in fuel, the nucleus of atom, and in foods. Or stored because of the work done on it: Stretching a rubber band. Winding a watch. Pulling back on a bow’s arrow. Lifting a brick high in the air.

Gravitational Potential Energy Potential energy that is dependent on height is called gravitational potential energy.

Gravitational Potential Energy A waterfall, a suspension bridge, and a falling snowflake all have gravitational potential energy.

Gravitational Potential Energy If you stand on a 3-meter diving board, you have 3 times the G.P.E, than you had on a 1-meter diving board.

Gravitational Potential Energy Objects with more mass have greater GPE Objects higher from the ground have more GPE. The formula to find GPE is GPE = mgh PEg = mgh

Example #1 A 4.0 kg rock is sitting on a 3.0-meter ledge. How much potential energy does the rock have?

Answer PEg = mgh PEg = 4.0kg x 9.81 m/s x 3.0m PEg = 1.2 x102 J

Example #2 Which object has the most potential energy? A 5.6kg rock at the top of a mountain 35 meters high, or a 5.6kg rock at the top of a mountain 55 meters high?

Answer The rock at the top of the mountain 55 meters high.

Elastic Potential Energy Energy that is stored due to being stretched or compressed is called elastic potential energy.

Elastic Potential Energy (PEelastic) Depends on the distance compressed or stretched from its relaxed length. PEelastic = ½ kx2 PE elastic = ½ x spring constant x (distance stretched or compressed) Spring constants have units of N/m