Question
Question: Which of the following charging methods work without even touching the object to be charged to the o...
Which of the following charging methods work without even touching the object to be charged to the object used to charge it?
A. Charging by friction
B. Charging by contact
C. Charging by induction
D. All of these
Solution
When we bring a charged body in contact with an uncharged body, the uncharged body gets charged. We can even charge two bodies by rubbing them against each other. We can also charge a body without bringing it in contact with a charged body.
Complete answer:
Charge is that physical quantity on a matter, which gives it the electrical properties. A charged particle exerts an electric force on another charged particle. However, not all objects are charged. These objects are called electrically neutral objects. But, we can charge an electrically neutral object with the help of an already charged object.
The given question is asking which of the given methods in the options are used to charge an object with help of a charged object, without bringing them into contact. The method in which an object is charged with bringing it in contact with a charged body is called charging by induction. In this, we say that the charge is induced on the object.
We know that a charge exerts an electric force on other charges. We also know that every matter is made up of electrons, which are charged particles. Therefore, when we bring a charged body close (not in contact) to a neutral body, the electrons within the body react to the charge body and there is a separation of negative and positive charges.Then one side of this body is grounded so that the separated electrons go into the ground and the body become charged.
Hence, the correct option is C.
Note: Some students may argue that the body to be charged is brought in contact with the ground. However, we are only with the two bodies (charged and uncharged) not in contact and not with the ground. Charging by friction is a method in which a body is charged by rubbing it on another body.