Learn Class 8 Science - Some Natural Phenomena

What is Natural Phenomena? In general terms, the natural phenomenon is something that happens by itself. Like it does not need any human interference.

Meaning

  • It means any natural calamity that occurs itself.
  • LIKE: Earthquakes and lightning.

Charged objects

  • Such objects get set by rubbing.

Electrostatic force

  • It is considered as the attraction & repulsion force.
  • And which also includes the charged objects.

Static Electric Charge

  • The charge that does not move.
  • It occurs when two substances come in contact with each other.
  • It depends on two factors, i.e., temperature & humidity.

How do charges get transferred?

Many ways can help to transfer the charges. Such methods are below:

1. Induction:

  • The process results in shifting the electron's position.
  • There is no involvement of physical contact between the objects.

2. Conduction:

  • The transfer of changes happens with the help of a conductor.
  • It occurs when the two objects come in contact.

Electroscope:

  • The concept was given by 'Abraham Bennet' in 1787.
  • The device helps to know whether the object is charged or not.

Structure:

  • The glass jar comes in a vertical brass rod.
  • Rod gets inserted into the jar with the help of cork.
  • Brass rods consist of the brass disc.

Learning Videos for 8th Grade Science - Some Natural Phenomena

Some Natural Phenomena Sample Questions for Class 8

Question 1

The negative charge is gained on atom when _______ is _______.
A. Protons , lost
B. Electrons, gained
C. Electrons, lost
D. Protons, gained

Question 2

Which particles are equal in number in an atom?
A. Electron and proton
B. Electron and neutron
C. Proton and neutron
D. Electron, proton and neutron

Question 3

Which of the following particle in atom has no charge on it?
A. Electron
B. Neutron
C. Proton
D. Nucleus

Question 4

The transfer of charges from charged object to earth via a metal rod is called as ________
A. Charging
B. Decharging
C. Earthing
D. Discharging

Question 5

When glass rod is rubbed with silk cloth then silk cloth gains ______ charge. When ebonite rod is rubbed with wool then wool cloth gains ________ charge.
A. Negative , Positive
B. Positive, Positive
C. Negative, Negative
D. Positive, Negative