Question

Which of the following is observed when a charged plastic rod is brought near a neutral aluminum rod?
1. The rods repel each other
2. The rods attract each other
3. The rods do not move
4. The rods exchange charges

Answer 1

Correct Answer - Option 2 : The rods attract each other

The correct answer is option 2) i.e. The rods attract each other

CONCEPT:

​Object acquire charge by three methods:

• ​Charging by friction: When two objects are rubbed, due to friction there occurs a charge transfer. 
  • An object loses its electrons, while the other object gains electrons.
  • The object that loses electrons becomes positively charged and the object that gains electrons becomes negatively charged.
• Charging by conduction: In this method, a charged conductor is brought in contact with another neutral body.
  • The neutral body acquires a charge such that the measure of charge on the neutral and charged conductor is the same.
• Charging by induction: This method is used to charge an object without actually touching the charged object.
  • The charged object is brought near the uncharged object. The end of the uncharged object near the charged object develops a charge of the opposite polarity. 

EXPLANATION:

• When a charged plastic rod is brought near the neutral rod, the ends of the rod near the plastic rod develop a charge of opposite polarity (due to induction).
• As a result, unlike charges tend to attract each other.
• So, it will be observed that the rods attract each other.