SSLC (English Medium) Class 9 - Tamil Nadu Board of Secondary Education Question Bank Solutions for Science

What is the difference between electromagnetic force and potential difference?

The force between two parallel wires carrying currents has been used to define ______.

Electric lines of force are ______ lines.

Name the force which acts between two point charges to obey Newton’s third law.

Define the following: 

Electric force

What are natural magnets?

Permanent magnets are made of hard magnetic materials like alnico.

Total internal reflection will occur if the angle of reflection is ______.

We can see objects because of ______.

The angle of incidence is equal to the angle of reflection for perfect reflection. 

______ is greater for liquids than solids and it is maximum in gases.

When heat energy is added to a substance, the kinetic energy of its particles ______ and so the particles move at a higher speed.

Explain the following effects of heat.

Expansion

How is matter classified?

Gold foil alpha particle scattering experiment was performed by ______.

In Rutherford’s experiment, the bouncing of alpha particles suggests that the nucleus of an atom is negatively charged.

Rutherford’s model of an atom has a very small ______ at the center.

What is the correct procedure for mixing acid and water? Why?

“All acids contain one or more hydrogen atoms, but not all substances containing hydrogen are acids.” Support this statement with examples.

______ & ______ metals do not react with HCl or HNO₃.