Question

sam used an electroscope to test a charged body first touch to the brass disk on a electrictroscope with a chargered glass rod the leavesof the electroscope became positively charged and diverged next on touching the disc of the electroscope with the object to be tested he observed that the leaves of the electroscope collapsed can you help him draw the correct conclusion​

Answer 1

Answer:

Aim: To see the working of an electoscope

Materials Required: ebonite rod , leave , electoscope

Procedure:

Rub an ebonite rod with leave and touch the brass discof an electoscope with it.

Observation:

On touching the charged body with the brass cap, the gold leaves diverge (open up), showing that both the leaves carry the same charge. This happens because the negative charge from the ebonite rod gets transferred to the gold leaves. Now bring a positively charged glass rod rubbed with silk and touch the disc with it. What do you notice now? The gold leaves fold back, showing that there is no charge on them. This happens as the negative charge on the gold leaves gets neutralised with the positive charge from the glass rod.

Answer 2

The correct conclusion is that the electroscope becomes discharged when the disc of the electroscope is touched with the object to be tested.

• When a glass rod is touched to the brass disk on an electroscope, both the leaves of the device acquire a positive charge.
• Since like charges repel each other, the leaves of the electroscope diverge.
• Next, when the testing object is touched, the leaves collapse. This is possible only when the leaves lose their acquired positive charge.
• This is possible when either the testing object is negatively charged or it is an uncharged conductor.
• The electrons from the testing object travel to the leaves and neutralize the excessive protons in the leaves.