Which of the following instruments can be used to compare the relative magnitudes of the charge on given bodies?
A) The electrophorus
B)Ebonite rod
C)Gold-leaf electroscope
The correct answer and explanation is:
The correct answer is C) Gold-leaf electroscope.
An electroscope is a scientific instrument used to detect the presence and measure the magnitude of electric charge on a body. It works based on the principle of electrostatic repulsion. The device consists of a metal rod connected to two thin leaves (usually made of gold or aluminum) which hang at the bottom. When a charged object is brought close to the electroscope, the charges on the metal rod induce like charges on the gold leaves, causing them to repel each other. The amount of repulsion between the leaves can be used to infer the relative charge on the object.
To compare the charge on two given bodies using an electroscope, the following steps are typically followed:
- Charge the electroscope: A known charge is placed on the electroscope, either by direct contact with a charged object or induction.
- Bring the first object near the electroscope: The first body is brought near the electroscope, and the deflection of the leaves is observed. This indicates the interaction between the charges.
- Bring the second object near: After observing the deflection with the first object, the second object is then brought close to the electroscope. The degree of deflection compared to the first object indicates whether the second body has more or less charge.
The Gold-leaf electroscope works because of the way charged bodies influence one another through electrostatic forces. The greater the charge on an object, the more significant the repulsion between the leaves. By observing and comparing the deflections when different objects are brought near, the relative charges of the objects can be compared.
The Electrophorus (A) is used to generate a charge but not specifically to compare magnitudes of charge, and the Ebonite rod (B) is a type of charged material but does not measure or compare charge magnitudes on other bodies.