Chapter 4: Section 2.  Machine- device that makes doing work easier ◦ They change the way a person does work, not the amount of work that needs to be.

Slides:

Advertisements

Similar presentations

How do machines work?.

Advertisements

5.2 Using Machines.

Chapter 4.2 How Machines Do Work?. - How Machines Do Work Input and Output Work The amount of input work done by the gardener equals the amount of output.

Today’s Agenda…9-16 Bellringer: What are the two conditions that must be met for something to be work? Finish notes on Work (Study Pack #17) Practice calculating.

Chapter 5 Lesson 2.

HOW MACHINES DO WORK? Key Concepts How do machines make work easier? What is a machine’s mechanical advantage? How can you calculate the efficiency of.

How Machines Do Work Outline Notes Pages

Chapter 14 Work & Simple Machines 4/12/2017 2:57 PM

 A machine is a device that makes doing work easier.  Machines can be simple.  Some, like knives, scissors, and doorknobs, are used everyday to make.

Chapter 15 Simple Machines.

Chapter 5 Work and Machines

Machines Machine: a device that makes doing work easier by: a. changing the amount of force needed b.the distance which force is exerted c. the direction.

CHAPTER 5: WORK AND MACHINES. WORK WORK IN THE SENSE OF SCIENCE IS DIFFERENT THAN WHAT MOST PEOPLE CONSIDER WORK AS BEING. WORK IN THE SENSE OF SCIENCE.

Using Machines Chapter 14 Lesson 2 432, 433, and 435

Work & Machines Chapter 5. Free Template from 2 Section 1: Work A.Work – transfer of energy that occurs when a force makes an object.

Chpt. 5—Work and Machines

Work and machines Machines make jobs easier. Machine – a device that helps do work by either changing the size of a force or changing the direction of.

Work and Machines What is a machine??.

Work and Machines Chapter 5 Sec 2. What is a Machine?  Any device that makes work easier.

Ch. 5 – Work & Machines I. Work Exerting a force over a certain distance;a form of energy(SI units = Joules)A. Work: 1. For work to be done an object must.

Chapter 5 Work & Machines

Machines, Mechanical Advantage and Efficiency. What is a Machine?  A machine makes work easier and more effective.  A machine never changes the amount.

Work and Machines. Machines Do Work  A Machine is a device that changes a force.  Ex. A Jack used to change a tire.  Machines make work easier to do.

Work and Machines Chapter 5 Section 1.

1 Simple Machines 2 History of Work Before engines and motors were invented, people had to do things like lifting or pushing heavy loads by hand. Using.

Chapter Work in Mechanical Systems Principles of Technology I Edinburg North High School.

Work Work: using a force for a distance W = F x d

What is a machine? A machine is a device that makes doing work easier. Machines can be simple. Some, like knives, scissors, and doorknobs, are used everyday.

Machines What is a machine? How do you calculate the M.A. and Efficiency of a machine?

Physical Science Chapter 5 Work and Machines 1 Note to self: Find videos.

Work, Power, and Machines Glencoe Chapter 5. A. Work is the transfer of energy that occurs when a force makes an object move. 1. For work to occur, an.

Work and Machines. What is a machine? A device that allows you to do work in a way that is easier and more effective.

Section 5-2.  The work done by a machine is work output. Work output = resistance force x resistance distance.  The work done on a machine is work input.

How Machines Do Work: Advantageous and Efficient Notes.

Warm Up: 1/14/13  Give an example of a machine you use on a daily basis. Then say how you thinks it helps to make work easier.

Work and Machines Chapter 5. What machines do you use in your life to help you do some type of work?

Work and Simple Machines Mandy Ennis Meeks Baldwin Arts and Academics Magnet School.

How Machines do WORK A Machine – is a device that allows you to do work in a way that is easier or more effective. INPUT FORCE – is the force you exert.

Warm-up for May 19, 2015 Textbook page 215 : Numbers 3 thru 8.

Simple Machines Chapter 14. What do All These Things Have in Common?

Machines A device that makes work easier

I. Introduction to Machines Machines Force Work Mechanical Advantage

Introduction to Machines Force Work Mechanical Advantage

Simple Machines Device that makes doing work easier is a machine

Chapter 6 Work and Machines Section 2 – Using Machines

Using Machines.

Chapter 14 Section 2.

How Machines Do Work Chapter 12 Section 2.

Machines - Ch. 7 I. Introduction to Machines (p ) Machines

REVIEW Work is done whenever a force moves an object over a distance.

Work = when a force is applied on an object and it moves in the direction of the force.

Chapter 5 Work and Machines.

Mechanical Advantage and Efficiency

6.2 – Using Machines.

Bell Ringer What is the formula for work?

Why we use machines.

Work and Machines Work: is the transfer of energy that occurs when a force makes an object move For work to be done, a force must make something move.

How do machines do work? 12-2.

Science Chapter 5 Section 2

Chapter 5 Work and Machines.

Chapter 5.2 Physical Science WZPP ps Ok web post

Introduction to Machines Machines Force Work Mechanical Advantage

1. How would the effort exerted by a backpacker over level ground compare to the effort in climbing a steep hill? 2. How would the weight of the backpack.

Machines - Ch. 7 I. Introduction to Machines (p ) Machines

Chapter 14 Section 2.

Using Machines.

How Do Machines Work Chapter 4 Section 2.

Presentation transcript:

Chapter 4: Section 2

 Machine- device that makes doing work easier ◦ They change the way a person does work, not the amount of work that needs to be done

 When using a machine, the output work can never be GREATER than the input work ◦ A machine cannot do more work than you put in! ◦ Law of conservation of energy ◦ Do not get work confused with force!

 MA = output force = Newtons input force Newtons Or: MA = F out F in The UNITS cancel out!

 F in = Input force- the effort, or force you exert on a machine  F out = Output force-the force exerted by the machine

 Changing the amount of force needed  Changing the distance the force covers  Changing the direction of the force

◦ Some machines allow you to exert a smaller force over a longer distance ◦ Output force > input force, resulting in a MA > 1 ◦ Ex: a ramp Output force = 500N = 10 Input force 50N

 Some machines allow you to exert your force over a shorter distance  Output force < Input force, resulting in a MA < 1 ◦ Ex. A rake Output force = 10N = 0.1 Input force 100N

 Some machines allow you to change the direction of the input force  Output force = input force, resulting in MA = 1  Ex. pulley Output force = 50N = 1 Input force 50N

Efficiency = output work input work x 100% Or: Eff = Wout x 100% Win Answer will always be in a percentage!

W out = 4500 J W in = 7500 J Eff = _____ Eff = Wout x 100% Win Eff = 4500 J x 100% 7500 J Eff = 0.6 x 100% Eff = 60%

 Friction – reduces efficiency by converting some work into heat. ◦ The efficiency of a real machine is always less than 100% because of friction. ◦ Only ideal machines are 100% efficient  Oil, or another lubricant can increase efficiency by reducing the number of contact points between surfaces.