Access Prior Knowledge Lesson 4: What are simple machines?

Opening ActivityOpen Science textbook to page 426.Open Science folder to review vocabulary words and outline for the chapter.Open Workbook to page 132A.Open Science journal and answer the following questions:1- Explain Newton's three laws of motion?Review Content Cards and Q-Cards in bin, sharing with partners quizzing each other quietly.Log in to clickers using student ID number.Be ready to review home learning when timer goes off.

Don't forget to write your home learning in your agenda page 133A.

Do you agree with the statement?

Machines decrease the amount of work that has to be done.

YES NO

Do you agree with the statement?

A pulley makes work easier by changing the direction of the force.

YES NO

Do you agree with the statement?

Inclined planes help you use less force over a shorter distance.

YES NO

Do you agree with the statement?

A compound machine uses at least two simple machines to do work.

YES NO

Machines and Work

Work is done when a force moves an object; a machine can change the direction or amount of force needed to do work but doesn’t make work less.

Simple machines have only a few parts, for example pulley, wheel and axel, lever, and inclined plane.

Pulley

It has a rope or cable and a wheel with grooves that make work easier by changing the direction of the force.

BRAIN POP: Pulleys

Wheel and Axle

A circular shape with a straight bar that reduces the amount of force needed to do work, for example doorknob or steering wheel of a car.

BRAIN POP: Wheel and Axle

Lever

A stiff bar that moves around a fixed point called the fulcrum, which reduces the amount of force you need to do the work.

A stiff bar that moves around a fixed

point called the fulcrum, which reduces the amount of force you need to do the work.

BRAIN POP: Levers

Inclined Plane

A flat surface with one end higher that the other, some examples are a doorstop, ramp and screws.

It's easier to push a box up a ramp than lift it straight up.

BRAIN POP: Inclined Plane

Complex Machines

A complex machine uses two or more simple machines that can use many forces to do work, some examples are car, go-cart and sailboat.

TextQuest

Answer in your Science Journal

1. How do pulleys help people do work?

2. Where should force be applied to a lever?

3. Which complex machine uses mainly human force to operate the simple machines in it?

4. What are two examples of a wheel and axle that can make work easier?

Don't forget to write your home learning in your agenda page 133A.