CBSE Important Questions Class 6 Science Chapter 4 – Exploring Magnets
Class 6 Science Chapter 4 Exploring Magnets is part of the new NCERT textbook Curiosity. It introduces students to magnets and their properties. Students learn that a magnet has two poles, North and South, that like poles repel and unlike poles attract, that a freely hanging magnet always rests in the north-south direction, and how a compass works. They also learn which materials are attracted by magnets, how to find the poles of an unknown magnet, and how to store magnets properly.
These CBSE important questions for Class 6 Science Chapter 4 cover identifying magnets by repulsion, comparing the strength of magnets using iron filings, finding the North pole of an unmarked magnet, the correct way to store bar magnets, what happens when a magnet is cut in half, and why wood does not block a magnetic field. Every question has a clear step-by-step answer in simple English with figures, so students can practise on their own, parents can check the working, and teachers can use them for class tests. A free printable PDF of these important questions is also available on this page.
Q1. In the given diagram, when object P was placed near object Q, the ball was pushed off the table. This indicates that objects P and Q are, respectively
(a) Steel, Plastic
(b) Nickel, Magnet
(c) Iron, Steel
(d) Magnet, Magnet
Answer: (d) Magnet, Magnet
Object Q was pushed away when P came near it. Pushing away is repulsion, and only two magnets can repel each other (when like poles face each other). A magnet can attract iron, steel or nickel, but it cannot push them away. So both P and Q must be magnets.
Q2. Three magnets A, B and C were dipped one by one in a heap of iron filings. The figure shows the amount of iron filings sticking to them. Based on your observation, identify which magnet is the strongest and explain the reasoning behind your conclusion.
Answer: Magnet A is the strongest. The strength of a magnet is judged by how much magnetic material it can attract. Magnet A has the largest amount of iron filings sticking to it, especially at its ends (the poles), so it has the greatest magnetic force. Magnet C has the least filings, so it is the weakest.
Q3. You are given a bar magnet, but its poles are not marked. How can you identify its North pole using another magnet whose North and South poles are clearly marked? Explain the principle behind your method.
Answer: Bring the North pole of the marked magnet near one end of the unmarked magnet.
• If that end is pushed away (repelled), it is the North pole of the unmarked magnet.
• If that end is pulled towards it (attracted), it is the South pole, and the other end is the North pole.
The principle is: like poles repel each other and unlike poles attract each other. Repulsion is the surest test, because a magnet attracts both the unlike pole of another magnet and ordinary iron, but it repels only the like pole of another magnet.
Q4. Three magnets A, B and C were dipped one by one in a heap of iron filings. The figure shows the amount of iron filings sticking to them. The strength of these magnets will be
(a) A > B > C
(b) A < B < C
(c) A = B = C
(d) A < B > C
Answer: (a) A > B > C
The more iron filings a magnet attracts, the stronger it is. Magnet A has the most filings, B has fewer and C has the least. So the order of strength is A > B > C.
Q5. The North pole of a magnet can be identified by
(a) Another magnet having its poles marked as North pole and South pole.
(b) Another magnet, no matter whether the poles are marked or not.
(c) Using an iron bar.
(d) Using iron filings.
Answer: (a) Another magnet having its poles marked as North pole and South pole.
We need a magnet whose poles are already known. The end of the unknown magnet that is repelled by the marked North pole is its North pole. An iron bar or iron filings are attracted by both poles, so they cannot tell us which pole is which.
Q6. The arrangements to store two magnets are shown by figures (a), (b), (c) and (d). Which one of them is the correct arrangement?
Answer: (b)
Bar magnets should be stored in pairs with their unlike poles next to each other (N of one beside S of the other), separated by a piece of wood, and with a piece of soft iron across each end. Only figure (b) shows this arrangement. Storing magnets this way stops them from losing their magnetism.
Q7. Why does wood not stop the magnet's effect on the compass? What materials might block or interfere with a magnetic field?
Answer: Wood is a non-magnetic material. A magnet's force passes straight through non-magnetic materials such as wood, paper, plastic and glass, so the compass needle still moves when a magnet is brought near with wood in between.
Magnetic materials such as iron, steel, nickel and cobalt can block or disturb a magnetic field. If an iron sheet is placed between the magnet and the compass, the effect on the needle becomes much weaker.
Q8. What would happen if you cut a bar magnet in half? Would you end up with a separate north pole and south pole, or would each piece still have both poles?
Answer: If a bar magnet is cut into two pieces, we get two smaller magnets. Each piece has its own North pole at one end and South pole at the other end.
We never get a piece with only a North pole or only a South pole. This shows that magnetic poles always exist in pairs, and a single pole cannot be made by breaking a magnet.
Q9. If Earth's magnetic field were to suddenly change direction, how would this affect sailors using a compass? What other methods could they use to find their way?
Answer: A compass works because its needle lines up with the Earth's magnetic field. If the field suddenly changed direction, the compass would point the wrong way and sailors could not trust it.
Instead they could use the Sun, Moon and stars to find directions (this is called celestial navigation). Today they can also use GPS and other electronic systems that do not depend on the Earth's magnetic field.
Q10. How can you use repulsion to identify if an object is a magnet?
(a) By checking if it attracts a paper clip
(b) By seeing if it repels other magnets with the same pole
(c) By seeing if it is made of metal
(d) By checking its colour
Answer: (b) By seeing if it repels other magnets with the same pole
Only a magnet can repel another magnet. If the object pushes away the like pole of a known magnet, it must be a magnet. Attracting a paper clip is not a sure test, because an unmagnetised iron bar is also attracted to a magnet.
Q11. What happens when the two north poles of two magnets are brought close to each other?
(a) They attract
(b) They repel
(c) They neither attract nor repel
(d) They form a new pole
Answer: (b) They repel
Like poles repel each other. When two North poles come close, they push each other away. Unlike poles (North and South) attract each other.
Q12. If you want to test the poles of an unknown magnet, how can you determine which end is the north pole and which is the south pole using another known magnet?
(a) On placing the north pole of the known magnet near the ends of the unknown magnet, the end that attracts will be the south pole.
(b) On placing the north pole of the known magnet near the ends of the unknown magnet, the end that attracts will be the north pole.
(c) On placing the south pole of the known magnet near the ends of the unknown magnet, the end that attracts will be the south pole.
(d) On placing the south pole of the known magnet near the ends of the unknown magnet, the end that repels will be the north pole.
Answer: (a) On placing the north pole of the known magnet near the ends of the unknown magnet, the end that attracts will be the south pole.
Unlike poles attract. So the end of the unknown magnet that is pulled towards the known North pole must be its South pole, and the other end is its North pole.
Related Study Material on Extramarks
- CBSE Important Questions Class 6 Science Chapter 1
- CBSE Important Questions Class 6 Science Chapter 2
- CBSE Important Questions Class 6 Science Chapter 3
- CBSE Important Questions Class 6 Science Chapter 5
- CBSE Important Questions Class 6 Science Chapter 6
- CBSE Important Questions Class 6 Science Chapter 7
- CBSE Important Questions Class 6 Science Chapter 8
- CBSE Important Questions Class 6 Science Chapter 9
- CBSE Important Questions Class 6 Science Chapter 10
- CBSE Important Questions Class 6 Science Chapter 11
- CBSE Important Questions Class 6 Science Chapter 12
Q.1 Describe the materials under the following headings with examples of each:
(i) Appearance
(ii) Hardness
(iii) Solubility
(iv) Transparency
(v) Floating property
Marks:1
Ans
(i) Appearance
The appearance of the material is compared in terms of colour, lustre, texture or physical state. A metal spoon shines, whereas a wooden spoon does not. Materials that have lustre are called metals. E.g: copper, aluminium, gold etc.
(ii) Hardness
Soft materials: The materials that can be compressed or scratched easily are called soft. For example, cotton, sponge.
Hard materials: The materials that cannot be compressed or scratched easily are called hard. For example, iron
(iii) Solubility:
Substances that disappear or dissolve completely in water are called soluble substances. For example, salt, sugar etc.
The substances that do not dissolve completely in water even after stirring for a long time are called insoluble substances. For example, chalk powder, saw dust etc.
(iv) Transparency
Transparent Materials: Substances through which things can be seen are transparent materials. For example, glass, water etc.
Opaque Materials: Substances through which things cannot be seen are opaque materials. For example, wood, iron etc.
Translucent Materials: The materials through which objects can be seen, but not clearly are known as translucent materials. For example, butter paper etc.
(v) Floating property:
Some objects float on water while another sink in it. An object will float or sink in water depends on whether it is lighter or heavier than water. Materials lighter than water floats, e.g., plastic, pencil etc. Materials heavier than water sinks, e.g., iron nail, steel etc.
Q.2 Which of these is not soluble in water?
(a) Oxygen
(b) Coconut oil
(c) Salt
(d) Vinegar
(i) Only (a)
(ii) Only (b)
(iii) (a), (c) and (d)
(iv) (b) and (d)
Marks:1
Ans
Oxygen, salt, and vinegar are soluble in water. Coconut oil is less dense than water. Hence, it floats on water and is insoluble in it.
Q.3 Kerosene and petrol do not dissolve in water. They are called
(a) immiscible liquids
(b) liquid solvents
(c) liquid solutes
(d) miscible liquids
Marks:1
Ans
(a) immiscible liquids
Liquids like petrol, kerosene, etc. which do not mix with water are called immiscible substances. Immiscible liquids when mixed, form separate layers.