SSLC (English Medium) Class 8 - Tamil Nadu Board of Secondary Education Question Bank Solutions for Science

How does carbon dioxide react with the following?

1. Potassium
2. Lime water
3. Sodium hydroxide

Define the following.

Specific heat capacity

Friction depends on the ______ of two surfaces in contact.

Analogy

Objects placed at rest on earth: ______:: Bodies slide over the surface on other body: ______.

Assertion: Friction always opposes the motion.
Reason: Whenever one surface moves or tries to move over another surface, the force of friction starts acting on the surfaces.

Assertion: We can live very happily if friction is not present in nature.
Reason: The airplane shape is streamlined to reduce the effort of frictional force.

Assertion: There is a danger of a vehicle skidding on a wet road.
Reason: The tires of the vehicle lose their grip on the road due to an increase in friction due to the presence of water on the road.

In dispersion, the color of light that will bend more is ______.

The periscope is an optical device with a polished surface that reflects the light falling on it.

Curved mirrors have surfaces that are spherical, cylindrical, parabolic, and ellipsoid.

Assertion: We can see the rainbow in the sky when the rain starts falling after a spell of bright sunlight.
Reason: The rainbow is formed due to the dispersion of light.

What is a rainbow?

Electroplating is based on ______ effect of electricity.

An electrolyte ______.

A layer of zinc-coated over iron. Why?

The time taken for one complete vibration is called its ______.

What are the symptoms of hearing loss?

What is meant by audible sound?

______ became the first Indian woman astronaut to go to space.

Write about Sunitha William’s work at NASA.