Science - Teachers Sri Lanka
Science - Teachers Sri Lanka
Science - Teachers Sri Lanka
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High Voltage<br />
Cathode with a slit<br />
Anode<br />
production of possitive rays<br />
Neutron<br />
Possitively charged particles named α particles are emitted from radio active sources.When<br />
fall on to the instrument to detect charged particals, it causes a deflection.(Fig. a)<br />
In 1932 James Chadwick conducted an experiment form which it was founded that when a<br />
thin Berylium sheet was place in between the radio active source and the detector no deflection<br />
was seen ( Fig. b)<br />
When a paraffin sheet was place between the Berylium α<br />
sheet and the detector tere was a<br />
deflection. (Fig. c)<br />
Source of<br />
Detector<br />
particals<br />
(a)<br />
(b)<br />
(c)<br />
Berylium plate<br />
Berylium plate<br />
particals<br />
Paraffin wax plate<br />
Shows deflection<br />
Possitive charge<br />
particals fall on<br />
detector<br />
No deflection is<br />
shown<br />
charged particals are<br />
not falling on the<br />
detector<br />
Shows a deflection<br />
charged particals<br />
fall on the detector<br />
Chargeless Neutrons Particals with possitive charge<br />
(d)<br />
14
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