Question

When a charged body is brought in contact with the metal disc of an uncharged electroscope, the gold leaves diverge. Which property of the charge is responsible for it? 3 6. A solid block weighing 200 N is in the shape of a cuboid with dimensions 20 cm x 10 cm x 10 cm. It is placed on the surface of a table, first with its square base and then with its rectangular base. In which case will it exert minimum pressure? Calculate the minimum pressure exerted by it in that case. ​

Answer 1

Answer:

Hint: Electroscope is a device used for detecting the presence of electric charges by attraction or repulsion. It also determines the type of charge whether it is a positive or negative charge. In this device, two pieces of gold leaves are enclosed in a glass-walled chamber.

Explanation:

Step I:

In an electroscope, there is a process to determine the type of charge and hence the effect on divergence. It is already given that the charged body increases the divergence of the electroscope. Divergence in a gold leaf electroscope basically indicates the amount of charge transferred from any external source to the gold leaf.

Step II:

Suppose if the negatively charged body is brought near the electroscope, the divergence increased. It happened because the electrons from the gold leaves get shifted due to induction. The amount of negative charge increases as like charges repel each other. The divergence will also increase as it shows the amount of charge transferred.

Step III:

In an electroscope, if the object has a positive charge then it will pull up electrons up to the top terminal. But if the object has a negative charge, then it will repel electrons from the top terminal.

∴  If the charged body is brought near the negatively charged electroscope, its divergence will increase. Note:

There can be a question as to why there is only a gold leaf used in an electroscope for determining the presence of charges? This is because gold is a metal that is highly malleable. This means that it can be converted into very thin, small, and light sheets to be enclosed in the chamber.