Life Processes — Science STD 10 — Question

What happens when a ray of light is incident normal to the interface between two media? Draw the corresponding neat and labelled diagram.

1. Write a food chain comprising all the given organisms?
2. Which organisms in the food chain are (i) herbivore, and (ii) carnivores?
3. Which organisms are (i) predators, and (ii) prey?
4. Which organisms can trap solar energy to make food?
5. Which organism is a secondary consumer?

Explain the nature and scope of disaster of flood with the help of points given beside.

State one use each of the following metals:
Copper, Aluminium, Iron, Silver, Gold, Mercury

Read the following paragraph and answer the questions:
If heat is exchanged between a hot and cold object, the temperature of the cold object goes on increasing due to gain of energy and the temperature of the hot object goes on decreasing due to loss of energy.

The change in temperature continues till the temperatures of both the objects attain the same value. In this process, the cold object gains heat energy and the hot object loses’ heat energy. If the system of both the objects is isolated from the environment by keeping it inside a heat resistant box (meaning that the energy exchange takes place between the two objects only), then no energy can flow from inside the box or come into the box.
(1) Heat is transferred from where to where?
(2) Which principle do we learn about from this process?
(3) How will you state the principle briefly?
(4) Which property of the substance is measured using this principle?

Sodium is always kept in kerosene.

How do butterflies contribute to environmental balance?

Explain the importance of good communication with others.

What are the advantages of hydroelectric power generation? 

 What is meant by latent heat? How will the state of matter transform if latent heat is given off?