What is the working principle of the electroscope, and how does the electroscope work

Uncharged, closed; Any kind of charge has an opening angle because two thin sheets with the same charge repels each other.

If it is not charged, it will open in contact with any charged body, because there is a current flowing to the electroscope and become charged.

If it is electrified, it will come into contact with an uncharged object, and the opening angle will become smaller, but it will not close. Because the charge flows to the uncharged object, there is a loss, the repulsive force becomes less, but there is still repulsion.

In contact with an object with the same charge, the opening angle: a, may become larger (because the charge of the charged body is more than that of the electroscope and the charge flows to the electroscope, and the repulsive force increases), b, it may become smaller, (because the charge of the charged body is less than that of the electroscope and the charge flows to the charged body, and the repulsive force decreases), c, it may also remain unchanged, (because the charge of the charged body is exactly the same as that of the electroscope, there is no current, and the repulsive force does not change).

In contact with objects with different charges, the opening angle must become smaller, but to what extent it depends on how much charge the charged body carries. a, if there is only a small amount of dissimilar charge, which is not enough to neutralize the charge of the electroscope itself, the opening angle will only become smaller and not closed; b, if there is a sufficient amount of dissimilar charge, the charge of the electroscope itself is neutralized first, and then the electroscope is charged with different charges, then the opening angle first becomes smaller to closed, and then opens due to re-charging (dissimilar charge); c, if the number of charges with dissimilar is the same as the number of charges of the electroscope, the charge happens to be completely neutralized, and the opening angle gradually decreases to just closed.

The working principle of the electroscope is made by using the principle of mutual repulsion of the same kind of charge in electricity. There are two pieces of metal that can be opened freely on each electroscope, when the electroscope is taken to check whether an object is charged or not and how much electricity it carries, if the object is not charged, there is no electricity transmitted here on the metal sheet, the metal sheet remains unchanged, when the object is electrified, there is electricity transmitted to the metal sheet of the electroscope, because there is the same kind of charge on the two metal sheets, it will produce a mutually repellent force, so that the two metal sheets are opened, when the object carries more electricity, the more electricity comes from the metal sheet, The greater the repulsive force, the greater the angle at which the metal sheet opens, and we can know how much the object is charged and how much it is charged by observing the opening of the metal sheet.

Junior High School Physics – Structure and Principles of Electroscope.

The principle of mutual repulsion of the same kind of charge.

Since the same charge repels each other, the foil will automatically separate and be stretched at an angle. According to the size of the two foils at an angle, the amount of charge charged by the object can be estimated.

When inspecting, the object is in contact with the metal ball (metal plate), if the object is charged, there is a part of the charge transmitted to the two pieces of metal foil, the metal foil is repelled by the same kind of charge, and the more charges, the greater the angle of opening; If the object is not electrified, the metal foil does not move.

When an object is known to be electrified, to identify the type of charge it is carrying, it is only necessary to contact the charged body with the metal ball to open the metal foil. Then, the metal ball of the electroscope is touched with a known enough positively charged object, and if the metal foil is opened at a greater angle, it means that the charge of the charged body is positive; Conversely, if the angle of opening of the foil decreases, or it closes first and then opens, it means that the charge of the charged body is negative.

Electrostatic induction is generated.

If a positively charged object approaches a metal ball of an uncharged electroscope, a negative charge is induced at the metal ball of the electroscope due to electrostatic induction, while the metal foil opens at a certain angle due to the positive charge;

If the electroscope is originally positively charged, due to the rotten induction of static electricity, the same charge repels each other, the amount of positive charge of the metal ball decreases, the amount of charge of the metal foil increases, and the opening angle increases;

If the electroscope is originally negatively charged, the dissimilar charges attract, the charge of the metal ball increases, and the charge of the metal foil may only decrease, it may decrease first, and then the positive charge increases, so its opening angle may only decrease, and may decrease first and then increase.