Write an activity to check the presence of charges on a body.
Answers
AN ACTIVITY TO CHECK THE PRESENCE OF CHARGES.
Aim: To find the presence of charge on a body
Materials required: A thermocol piece, a silver foil, a glass rod, a silk cloth, a stand.
Procedure:
- Make a small ball of thermocol piece.
- Wrap thin silver foil to cover the thermocol ball and suspend it from a stand with the help of a thread.
- Bring a glass rod which is rubbed with a silk cloth near the suspended ball. The thermocol ball get attracted towards the glass rod.
- Now touch the silver foil on the thermocol ball with a charged glass rod.
- Remove the glass rod from the ball and again rub it with silk cloth and bring it close to the suspended ball.
Observation:
We notice that in the first instánce the thermocol ball is attracted towards the glass rod and in the second instánce it moves away from the glass rod.
What could be the reason for this change in movement of the ball?
In the first case, when a charged body (glass rod rubbed with silk cloth) is brought near an uncharged body (thermocol) it induces an opposite charge in it and hence it gets attracted by the glass rod.
In second case we have charged the thermocol ball by touching it with a charged glass rod.
Hence when we brought the glass rod near the ball, the ball gets repelled by the glass rod, as both of them have similar charge.
Conclusion:
From the above experiment we can conclude that attraction is not a sure test to know the presence of a charge on a body
- ᴛᴀᴋᴇ ᴀ ꜱᴛʀᴀɪɢʜᴛ ᴛʜɪᴄᴋ ᴄᴏᴘᴘᴇʀ ᴡɪʀᴇ ᴀɴᴅ ᴘʟᴀᴄᴇ ɪᴛ ʙᴇᴛᴡᴇᴇɴ ᴛʜᴇ ᴘᴏɪɴᴛꜱ x ᴀɴᴅ ʏ ɪɴ ᴀ ᴇʟᴇᴄᴛʀɪᴄ ᴄɪʀᴄᴜɪᴛ, ᴀꜱ ꜱʜᴏᴡɴ. ᴛʜᴇ ᴡɪʀᴇ xʏ ɪꜱ ᴋᴇᴘᴛ ᴘᴇʀᴘᴇɴᴅɪᴄᴜʟᴀʀ ᴛᴏ ᴛʜᴇ ᴘʟᴀɴᴇ ᴘᴀᴘᴇʀ.
- ʜᴏʀɪᴢᴏɴᴛᴀʟʟʏ ᴘʟᴀᴄᴇ ᴀ ꜱᴍᴀʟʟ ᴄᴏᴍᴘᴀꜱꜱ ɴᴇᴀʀ ᴛᴏ ᴛʜɪꜱ ᴄᴏᴘᴘᴇʀ ᴡɪʀᴇ. ꜱᴇᴇ ᴛʜᴇ ᴘᴏꜱɪᴛɪᴏɴ ᴏꜰ ɪᴛꜱ ɴᴇᴇᴅʟᴇ.
- ᴘᴀꜱꜱ ᴛʜᴇ ᴄᴜʀʀᴇɴᴛ ᴛʜʀᴏᴜɢʜ ᴄɪʀᴄᴜɪᴛ ʙʏ ɪɴꜱᴇʀᴛɪɴɢ ᴛʜᴇ ᴋᴇʏ ɪɴᴛᴏ ᴛʜᴇ ᴘʟᴜɢ.
- ᴏʙꜱᴇʀᴠᴇ ᴛʜᴇ ᴄʜᴀɴɢᴇ ɪɴ ᴛʜᴇ ᴘᴏꜱɪᴛɪᴏɴ ᴏꜰ ᴛʜᴇ ᴄᴏᴍᴘᴀꜱꜱ ɴᴇᴇᴅʟᴇ.
