Presentation is loading. Please wait.

Presentation is loading. Please wait.

Machines & electromagnets

Similar presentations


Presentation on theme: "Machines & electromagnets"— Presentation transcript:

1 Machines & electromagnets
Introduce yourself as the facilitator and outline (briefly) your STEM background. Ask STEM Ambassadors (if present) to (briefly) introduce themselves and to say which STEM discipline/industry they are from.

2 Simple machines Have students name the different types of machines
Ask them for an example in real life. The lever is a long tool such as a pole or a rod put under an object to lift it. An axle is a rod or pole centred in the wheel that allows the wheel to turn around it. The inclined plane is simply a ramp. One end is higher than the opposite end. This allows things to go from a low place to a higher place or vice versa. The wedge is used to separate an object apart. This is needed to cut, tear or break something in two. The pulley is actually a version of a wheel and axle that is combined with a rope, chain or other cord to allow moving something up and down or back and forth. The screw is really a twisted inclined plane. It allows movement from a lower position to a higher position but at the same time it moves it in a circle.

3 Let’s identify each type of machine
Have the students identify each type of machine. 1 = Pulley 2 = Lever 3 = Wedge 4 = Screw 5 = Inclined plane 6 = Wheel & Axel 11/21/2018

4 Rube Goldberg’s machine
A Rube Goldberg machine, contraption, invention, device, or apparatus is a deliberately over-engineered or overdone machine that performs a very simple task in a very complicated fashion, usually including a chain reaction. The expression is named after American cartoonist and inventor Rube Goldberg (1883–1970). Rube Goldberg’s comics depicted simple tasks completed in a complex manner using engineered machines. His name was inducted in the Merriam-Webster dictionary in 1931 as an adjective defined as accomplishing something simple through complicated means. Rube Goldberg machines as such, require a general understanding of some basic engineering and science principles, as well as certain degree of ingenuity and innovation. The basic concept is that the machine does not use human interaction to fulfil its task, besides an initiation step. A key component to Rube Goldberg machines is the idea of troubleshooting. A machine will rarely work on its first trial run, and requires observation and technical know-how to determine what the problem is, and how to fix it. Rube Goldberg machines rely on the movements derived from the six simple machines.

5 Let’s look at an example machine
A great example of a Rube Goldberg machine can be found by searching “National Geographic Rube Goldberg Machine” or clicking this link: Have the students shout out which simple machines are shown whilst they watch the video.

6 Electromagnets & machines
We can enhance the basic components of a Rude Goldberg machine by including electromagnets to produce additional energy or electricity. A bicycle dynamo is a simple example of an electromagnet. How do dynamos work? A voltage is produced when a magnet moves in a coil of wire. This process is called electromagnetic induction. A generator inside the induces a current by spinning a coil of wire inside a magnetic field. As this happens, a potential difference is produced between the ends of the coil, which causes a current to flow. One simple example of a generator is the bicycle dynamo. The dynamo has a wheel that touches the back tyre. As the bicycle moves, the wheel turns a magnet inside a coil. This induces enough electricity to run the bicycle's lights.

7 Your turn to build your own machine!
Use simple machines to create a chain reaction! Objective Land the marble in the cup! Students will work in groups to build a machine that lands a marble in the cup. (Click slide to show animation of moving marble for an example). 11/21/2018 7

8 Scoring system for your machines
Use simple machines to create a chain reaction! Every Type of Machine Every Machine TOTAL 65 points Teams will earn the following points: 10 points for every type of machine they include in their design. 5 points for every machine. M M M 30 points 35 points 8

9 RAF examples: using a pulley
The RAF have some very heavy pieces of kit and equipment to move around. Sometimes heavy machinery is not available to help to move equipment – so other approaches need to be used. Pulleys are a great and effective way of moving heavy objects by using some simple physics! In the example here, the RAF are able to use a pulley system by redirecting and their combined or amplifying force. It helps reverse the direction of an individual's lifting force. As a user pulls a rope down, the pulley lifts the weight up. When two ropes and wheels are used, a pulley reduces the effort needed to lift a weight by half.


Download ppt "Machines & electromagnets"

Similar presentations


Ads by Google