Introduction - Section 1
Completion requirements
What are simple machines and how do they make work easier?
Targets
At the end of this unit, you should be able to answer the following questions:1. What are simple machines, and how do they make work easier?
1.1 What advantage do I get from using a lever?
1.2 How do wheels and rollers help move things from place to place?
1.3 What role do wheel and axle systems have in moving vehicles and devices?
Can you imagine how difficult it was to be a lumberjack in the days
without modern machines? First, you had to cut down big trees with only
axes and saws. Then, you needed to pull the logs out of the forest
with only the help of other lumberjacks and horses. It was dirty,
difficult, dangerous work.
Conditions have changed for loggers!
Now, modern logging machines are able to cut, move, and stack logs
quickly and safely. By using simple machine systems, modern machines
have improved our lives and made many tasks easier and safer.
Technology and Society Connection
Simple machines can be combined to make devices in ways limited only by human imagination. Some vehicles and devices are truly incredible, even unbelievable!
Let's explore the wild, weird world of machines with some questions to see if you believe them! Read these questions, think about the machine or device, and decide whether the question is true or false.
Incredible Machines: True or False?
Do you want to find out more about weird and interesting machines? Search the Internet or books and share your weird and interesting machine stories on our class discussion board for others to read.
Let's explore the wild, weird world of machines with some questions to see if you believe them! Read these questions, think about the machine or device, and decide whether the question is true or false.
Incredible Machines: True or False?
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The "Segway" is a two-wheeled device that allows the rider to go forward or backward by shifting body weight.
True! The Segway has computers and motors to keep it balanced. If you get on a Segway and lean forward, it senses your shift in weight and moves forward. To slow down, you only need to lean backward. Although the Segway has only two wheels, its balance is so good that tipping it over is almost impossible.
A Segway can be a fun way to get around - and fast at up to 20 km/hr! -
The largest dump truck in the world has tires that are more than 6 metres tall.
False! The largest dump truck in the world uses huge tires, but they are only 4 metres tall. The tires weigh 5300 kg (heavier than a female elephant!), cost about $42,000 each, and are attached to the axle using 47 nuts.
Courtesy of d10n2000/flickr
The Caterpillar 797 truck needs six tires because of the heavy loads it carries. These dump trucks get lots of use carrying oil sand in Northern Alberta.
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The first military submarine in the world was built in 1775, held only one person, and was powered by hand.
True! The "Turtle" was built as a way to attach bombs to the hulls of ships. The operator made the Turtle move by turning a crank attached to a small propeller.
The Turtle had a drill that was supposed to bore into a ship's hull; then, bombs could be attached. The Turtle made several attempts to attack ships, but it was never successful. -
The "Shweeb" is a method of transport where humans hang from a monorail travelling at up to 70 km/h in pedal-powered plastic tubes.
True! The Shweeb is a ride in New Zealand, but some people want to build Shweeb systems in cities.
Do you want to find out more about weird and interesting machines? Search the Internet or books and share your weird and interesting machine stories on our class discussion board for others to read.