List of top Science Questions

A freely falling object eventually stops on reaching the ground. What happenes to its kinetic energy?

Platinum, gold and silver are used to make jewellery.
Sodium, potassium and lithium are stored under oil.
Aluminium is a highly reactive metal, yet it is used to makeutensils for cooking.
Carbonate and sulphide ores are usually converted into oxides during the process of extraction.

Here is a crossword puzzle: Good luck!

a crossword puzzle
Across
3. Liquid waste products
4. Solid waste extracted in sewage treatment
6. A word related to hygiene
8. Waste matter discharged from human body
Down
1. Used water
2. A pipe carrying sewage
5. Micro-organisms which causes cholera
7. A chemical to disinfect water

In the circuit shown in Fig.

(i) Would any of the bulb glow when the switch is in the ‘OFF’ position?
(ii) What will be the order in which the bulbs A, B and C will glow when the switch is moved to the ‘ON’ position?

Will the compass needle show deflection when the switch in the circuit shown by Fig. is closed?

Will the compass needle show deflection when the switch in the circuit

Fig. shows four cells fixed on a board. Draw lines to indicate how you will connect their terminals with wires to make a battery of four cells.

Draw the circuit diagram to represent the circuit shown in Fig.

the circuit diagram

Draw in your notebook the symbols to represent the following components of electrical circuits: connecting wires, switch in the ‘OFF’ position, bulb, cell, switch in the ‘ON’ position, and battery

Which of the following distance-time graphs shows a truck moving with speed which is not constant?

Fig. shows the distance-time graph for the motion of two vehicles A and B. Which one of them is moving faster?

distance-time graph for the motion of two vehicles

How does the process of fertilisation take place in flowers?

Explain the difference between self-pollination and cross-pollination.

Sketch the reproductive parts of a flower.

State the main difference between asexual and sexual reproduction.

Describe the function of the heart.

Given below is a square of letters in which are hidden different words related to respiration in organisms. These words may be present in any direction — upwards, downwards, or along the diagonals. Find the words for your respiratory system. Clues about those words are given below the square.

a square of letters in which are hidden different words related to respiration in organisms

The air tubes of insects
Skeletal structures surrounding chest cavity
Muscular floor of chest cavity
Tiny pores on the surface of leaf
Small openings on the sides of the body of an insect
The respiratory organs of human beings
The openings through which we inhale
An anaerobic organism
An organism with tracheal system

Look at Fig. Mark where the heat is being transferred by conduction, by convection and by radiation.

Label Fig. of the digestive system

Distinguish between a parasite and a saprotroph.

A magnet was brought from different directions towards a toy boat that has been floating in water in a tub. Affect observed in each case is stated in Column I. Possible reasons for the observed affects are mentioned in Column II. Match the statements given in Column I with those in Column II.

Column I	Column II
Boat gets attracted towards the magnet	Boat is fitted with a magnet with north pole towards its head
Boat is not affected by the magnet	Boat is fitted with a magnet with South pole towards its head.
Boat moves towards the magnet if North pole of the magnet is brought near its head.	Boat has a small magnet fixed along its length.
Boat moves away from the magnet when North pole is brought near its head.	Boat is made of magnetic material.
Boat floats without changing its direction.	Boat is made up of non-magnetic material

Column I shows different positions in which one pole of a magnet is placed near that of the other. Column II indicates the resulting action between them for each situation. Fill in the blanks.