Sources of Energy | Activities in Text Book with Solution
Activity 14.3
Take a table-tennis ball and make three slits into it.
Put semicircular ( ) fins cut out of a metal sheet into these slits.
Pivot the tennis ball on an axle through its centre with a straight metal wire fixed to a rigid support. Ensure that the tennis ball rotates freely about the axle.
Now connect a cycle dynamo to this.
Connect a bulb in series.
Direct a jet of water or steam produced in a pressure cooker at the fins (Fig. 14.2). What do you observe?
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| Fig. 14.2 |
✅Answer: The bulb glows.
This is the model of turbine
for generating electricity. The simplest turbines have a moving part called a rotor-blade
(fan). The moving fluid spin the blades and impart energy to the rotor. It turns
the shaft of dynamo and convert mechanical energy into electrical
energy.