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प्रश्न
What is an electroscope? Describe the different stages of charging a gold leaf electroscope negatively with the help of a diagram.
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उत्तर
An electroscope is a device used to detect the presence of charge and the nature of a charge on the body.

The four stages of the charging a gold leaf electroscope by induction are :
(i) Bring a positively charged rod near the cap of an electroscope. The cap will acquire a negative charge on it by induction. The leaves will diverge
(ii) Earth the electroscope by touching the cap will finger.
(iii) Remove the finger and keep the positively charged rod as such.
(iv) Now, take away the rod. The leaves will diverge because of charges induced by induction.

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संबंधित प्रश्न
The strength of the electromagnet can be increased by
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You are required to make an electromagnet from a soft iron bar by using a cell, an insulated coil of copper wire and a switch.
- Draw a circuit diagram to represent the process.
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- State the polarity at the ends X and Y as the switch is pressed.
- Suggest one way of increasing the strength of electromagnet so formed.

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