• Activity 1
Internal combustion engines
Objective:
Students get acquainted with the principles and harmful effects of internal combustion
engines.
Materials and devices needed:
A model of the engines, computer, internet connection
Procedure/Task:
The driving force when driving a car is usually provided by internal combustion engines.
Their common feature is that combustion of fuel and work is carried out in the same space in
the engine cylinder.
They can be divided according to their functional principles into:
-
-
Otto-engines (petrol)
Diesel-engines
The Otto-engine combines fuel-air mixture into the cylinder and compresses it.
The gas mixture is switched on by an electric spark at an appropriate time.
The diesel engine puts clean air into the cylinder and compresses it. The injector sprays the
fuel at high pressure into the combustion chamber
where it ignites itself.
1. Intake
2. Compression 3. Ignition
4. Exhaust
Evaluation:
The teacher explains the working principles of internal combustion engines and demonstrates
them with the help of the models. Teacher emphasizes the basic differences between otto-
engines and diesel engines.
Using the Internet students find information about exhaustion of harmful gases, prepare notes
and demonstrate their findings using tables/graphs.
At the end of the lesson proper understanding is checked through quiz questions.
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