Question

Assertion: Mass of a body decreases slightly when it is negatively charged. Reason: Charging is due to the transfer of electrons.
(A) Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
(B) Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
(C) Assertion is correct but Reason is incorrect
(D) Assertion is incorrect but Reason is correct

Answer 1

Hint: The mass of the object is the total mass of each particle inside the object. Mass of the body is its internal property and it is not affected by gravity and other forces. The SI unit of mass is kg.

Complete step by step answer:
The electric charge of the body causes it to experience the force when an electric field is applied to it.
We know that there are two types of charges:
Positive charge: when electrons are lost, the body develops a positive charge.
Negative charge: when electrons are gained, the body develops a negative charge.
Charging of any body is the process of increasing or decreasing the number of electrons. The mass of the electrons is almost negligible. So when a negative charge is applied to a mass of a body, the electron on the body increases. The charge of an electron is: \[{{e}^{-}}=-1.6\times {{10}^{-19}}C\]. Now the body will be negatively charged. Electrons have some mass. Mass of the electron is: $m=9.1\times {{10}^{-31}}kg$. So as the number of electrons increases, its mass will also be increased and henceforth mass of a body will be increased.
An electrical charge is created when electrons are transferred to or removed from an object. Because electrons have a negative charge, when they are added to an object, it becomes negatively charged. When electrons are removed from an object, it becomes positively charged.
Therefore, the mass of a body increases when it is negatively charged and the charge is produced due to the transfer of electrons. So Assertion is incorrect but the reason is correct. Hence, option D. is correct.

Note: To solve this kind of question, we should know mass and matter. When electrons of the atoms are either donated or accepted, the number of the protons inside the atom changes. This results in the charging of the object.