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.

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 Chapter 4.
Energy.
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 Notes Chapter 5-2. Mechanical Kinetic Energy Amount of energy an object has based on motion Depends on the mass of the object.
Kinetic and Potential Energy
Chapter 5 Work, Energy, Power Work The work done by force is defined as the product of that force times the parallel distance over which it acts. The.
ENERGY Part I.
Chapter 5 – Work and Energy If an object is moved by a force and the force and displacement are in the same direction, then work equals the product of.
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.
WORK AND ENERGY 1. Work Work as you know it means to do something that takes physical or mental effort But in physics is has a very different meaning.
What is Energy? Energy is the ability to do work In other words, energy is transferred by a force moving an object through a distance (Work = Force x Distance)
Regents Physics Work and Energy. Energy and Work Energy is the ability to Work Work is the transfer of energy to an object, or transformation of energy.
ADV PHYSICS Chapter 5 Sections 2 and 4. Review  Work – force applied over a given distance W = F Δ x [W] = Joules, J  Assumes the force is constant.
Mechanical Energy Ch. 4. Energy Is the ability to do work. Energy = work Units = Joules (J) James Prescott Joule.
Energy Chapter 5 Section 2.
Work and Power Chapter 5. Work Work is done when a force causes a displacement in the direction of the force W = Fd (force and displacement parallel)
Unit 2 Lesson 2 Kinetic and Potential Energy
Mechanical Energy. Kinetic Energy, E k Kinetic energy is the energy of an object in motion. E k = ½ mv 2 Where E k is the kinetic energy measured in J.
Work and Energy Energy Chapter 5: Section 2. Learning Targets Identify several forms of energy Calculate kinetic energy for an object Distinguish between.
What do you think of when
Energy 4 – Elastic Energy Mr. Jean Physics 11. The plan:  Video clip of the day  Potential Energy  Kinetic Energy  Restoring forces  Hooke’s Law.
Work has a specific definition in physics. Work is done anytime a force is applied through a distance.
Sub title Potential Energy Work Work- Energy Theorem Kinetic Energy Power 200 Work-Power-Energy.
The unit to measure work is ___________ The two requirements: Example: How much work is done if the guy pushes with 40 N to move the 20 N box.
Work and Energy. Work is force x displacement Only the force parallel to the displacement applies to work Guy is pulling a sled with a force of 50 N at.
Instructions for using this template. Remember this is Jeopardy, so where I have written “Answer” this is the prompt the students will see, and where.
Work, Power, Energy. Work Concepts Work (W) ~ product of the force exerted on an object and the distance the object moves in the direction of the force.
Chapter 12 Work, Energy and Power. Energy Is the ability to do work Expressed in Joules (dzuls) Forms of energy: Mechanical, Heat, light, and Chemical.
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.
THERMAL Energy Chapter 5.
Work is only done by a force on an object if the force causes the object to move in the direction of the force. Objects that are at rest may have many.
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.
Energy – the ability to do work W = Fd = m a d V f 2 = V i 2 + 2a  x V f 2 - V i 2 = + 2a  x V f 2 - V i 2 = a  x 2.
Types of Energy March 1, 2016 Chapter 4.1. Meme Moment.
Energy Notes Energy is one of the most important concepts in science. An object has energy if it can produce a change in itself or in its surroundings.
1 PhysicsChapter 5 Work & Energy Sections:15-1 Work 5-2 Energy 5-3 Conservation of Energy 5-4 Work, Energy & Power.
Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Work Chapter 5 Definition of Work Work is done on an object.
Work and Energy Chapter 5. Work In physics: “the amount of energy transferred from one object to another” Measured in Joules (J) Mathematically: W = Fd.
Work Power Energy. Work Concepts Work (W) ~ product of the force exerted on an object and distance the object moves in the direction of the force. Work.
Potential and Kinetic Energy Understanding the cyclic nature of potential and kinetic energy.
Energy and Work. Work… Work = Force // x Displacement W = F // x d ** Remember that displacement is the distance AND direction that something moves. It.
Day 2:.
M.I.T. C.P. Physics ENERGY.
Unit 2 Lesson 2 Kinetic and Potential Energy
Definitions The scientific definition of work is a force exerted over a distance (work = force · distance) work - The scientific definition of energy is.
Energy.
1a i) KE = ½ x mass x speed2 1a i)
Unit 2 Lesson 2 Kinetic and Potential Energy
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.
Unit 2 Lesson 2 Kinetic and Potential Energy
KE and PE Practice Quiz Solutions.
Energy Chapter 4.
Describing Energy.
Energy Notes.
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 Chapter 4.
Work-Energy Theorem Energy is the ability to do work.
Work and Energy Energy.
Energy comes in many forms: mechanical, electrical , magnetic, solar,
ELASTIC FORCE The force Fs applied to a spring to stretch it or to compress it an amount x is directly proportional to x. Fs = - k x Units: Newtons.
Energy.
Work and Energy.
Work and Energy.
Mechanical Energy, Me (Units of joules (J))
Energy.
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.
Ch 8 Energy Notes ENERGY – 5.2 PPT.
Presentation transcript:

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.

Unit for Work is the Joule Work = Force x Displacement Work = Force x Displacement JouleNewtonMeter Nmkg m/s 2 m Work is only done on an object if the force is parallel to the object’s displacement.

Work = F x cosine Θ x D

Energy Energy is the ability to do work. Energy is expressed in Joules. Work and energy are interrelated. –Work must done on an object to get to it move. –Moving objects can do work.

Positive and Negative Work –Positive work is done on object when it moves in the same direction in which the force is exerted. The speed of the object increases. –A student pushes back on the sidewalk to increase the speed of his skateboard. –Negative work is done on an object when the force opposes the forward motion of the object. The speed of the object decreases. –A student uses the brake on his roller blades to slow down.

Kinetic Energy Kinetic energy is the energy of motion. –It can be calculated by using the following equation. KE = ½ mv 2 Joule = kg x (m/s) 2 Joule = kg x (m/s) 2 N = kg m/s 2 x m N = kg m/s 2 x m Nm = Joule Nm = Joule If the object’s mass is doubled then the kinetic energy is doubled but it the velocity is doubled the kinetic energy is quadrupled!

Potential Energy Potential energy is stored energy. –Anytime a particle or object is forced to maintain a position in which it would not naturally exist has potential energy. –This natiral position is known as equilibrium. Types of Potential Energy –Gravitational Potential Energy –Elastic Potential Energy –Electrical Potential Energy –Chemical Potential Energy

Elastic Potential Energy The energy stored in an elastic material

Elasticity Elasticity is the ability of a material to return to its original shape after being deformed. –F = kx F = Force (N) k = spring constant (N/m) x = amount spring or material is stretched or compresses. (m) – a negative x means the spring is compressed –A positive x means the spring is stretched.

Elastic Potential Energy The amount of elastic energy stored in a spring. –E e = ½ kx 2 expressed in Joules – E e = elastic potential energy k = spring constant x = degree spring is stretched or compressed x = degree spring is stretched or compressed

Gravitational Potential Energy PE = mgh mass x 9.8 m/s 2 x height mass x 9.8 m/s 2 x height

Work Energy Theorem Work causes a change in kinetic energy. Work = Δ energy W = ½ mv 2 final - ½ mv 2 initial W = ½ mv 2 final - ½ mv 2 initial Slowing down or increasing the speed of an object changes its kinetic energy. A force must be applied and thus work must be done to change the kinetic or potential energy of and object.

Power Rate in which work is done. Power is expressed in Watts – Watts = Joules/second – 1 horse power = 740 W