- A. wooden piece
- B. plain pins
- C. eraser
- D. a piece of paper
b. Plain pins
b. Plain pins
- A. Indians
- B. Europeans
- C. Chinese
- D. Egyptians
(c) Chinese
(c) Chinese
- A. North-east
- B. South-west
- C. East-west
- D. North-south
d. North-South
d. North-South
- A. used
- B. stored
- C. hit with a hammer
- D. cleaned
(c) hit with a hammer
(c) hit with a hammer
- A. speed
- B. displacement
- C. direction
- D. motion.
c. direction
c. direction
Oval shape, Disc Shape, cylindrical shape
magnetic materials
magnetic
lodestone
Two
Oval shape, Disc Shape, cylindrical shape
magnetic materials
magnetic
lodestone
Two
False – A cylindrical magnet has two poles.
True
False – Maximum iron fillings stick in the poles of a bar magnet when it is brought near them.
False – A. compass can be used to find north-south direction at any place.
False – Rubber is a non-magnetic material.
False – A cylindrical magnet has two poles.
True
False – Maximum iron fillings stick in the poles of a bar magnet when it is brought near them.
False – A. compass can be used to find north-south direction at any place.
False – Rubber is a non-magnetic material.
Iron, nail, pins,
needle
Rubber tube is a non-magnetic substance.
Iron, nail, pins,
needle
Rubber tube is a non-magnetic substance.
Lift, escalator, electromagnetic train,
Electromagnet is not used in an electric bulb.
Lift, escalator, electromagnetic train,
Electromagnet is not used in an electric bulb.
Attraction, repulsion, pointing direction,
Illumination is not a magnetic property.
Attraction, repulsion, pointing direction,
Illumination is not a magnetic property.
Like poles (N – N, S – S) repel each other.
Unlike poles (N – S, S – N) attract each other.
Like poles (N – N, S – S) repel each other.
Unlike poles (N – S, S – N) attract each other.
Magnets lose their properties if they are heated or dropped from a height or hit with a hammer.
Magnets lose their properties if they are heated or dropped from a height or hit with a hammer.
Place the iron needle on the table.
Take a bar magnet and place one of its poles near one edge of the iron needle.
Rub from one end to another without changing the direction of the pole of the magnet.
Repeat the process 30 to 40 times. The needle will be magnetized.
If it will not attract pin or iron fillings continue the same process for some more time.
Place the iron needle on the table.
Take a bar magnet and place one of its poles near one edge of the iron needle.
Rub from one end to another without changing the direction of the pole of the magnet.
Repeat the process 30 to 40 times. The needle will be magnetized.
If it will not attract pin or iron fillings continue the same process for some more time.
Electromagnets are used in electromagnetic trains.
Electromagnets are magnetised when current flows through them. When the direction of the current is changed, poles will be changed.
Magnets are attached at the bottom of the train and rail tracks.
The train is lifted from track up to 10 cm height by the property of the same poles repel each other.
By using attraction and repulsion at the same time between the magnets in tracks and bottom of train move forward.
The magnets are controlled by electricity.
There is no friction. So the train can easily attain a speed of 300 km/ h.
Electromagnets are used in electromagnetic trains.
Electromagnets are magnetised when current flows through them. When the direction of the current is changed, poles will be changed.
Magnets are attached at the bottom of the train and rail tracks.
The train is lifted from track up to 10 cm height by the property of the same poles repel each other.
By using attraction and repulsion at the same time between the magnets in tracks and bottom of train move forward.
The magnets are controlled by electricity.
There is no friction. So the train can easily attain a speed of 300 km/ h.
When we place the bar magnet in iron fillings a large number of iron fillings stick on the two ends of the bar magnet. These ends are poles of the magnet.
Poles will attract more iron filings. Because poles have high magnetic strength.
b. Which part of the bar magnet attracts more iron filings? Why?
The more iron filings are attracted by the poles of the magnet because the poles have more concentrated magnetic power.
When we place the bar magnet in iron fillings a large number of iron fillings stick on the two ends of the bar magnet. These ends are poles of the magnet.
Poles will attract more iron filings. Because poles have high magnetic strength.
b. Which part of the bar magnet attracts more iron filings? Why?
The more iron filings are attracted by the poles of the magnet because the poles have more concentrated magnetic power.
Take a bar magnet.
Tie it in a thread.
Dip the tied magnet into the glass of water.
The pins are attracted by the magnet.
Now take out the magnet from the glass of water.
Collect the pins from the magnet.
Take a bar magnet.
Tie it in a thread.
Dip the tied magnet into the glass of water.
The pins are attracted by the magnet.
Now take out the magnet from the glass of water.
Collect the pins from the magnet.
- A. Iron
- B. Cobolt
- C. Nickel
- D. Rubber
(d) Rubber
(d) Rubber
- A. dipped in water
- B. dipped in oil
- C. heated
- D. in freezer
(c) heated
(c) heated
Man-made magnets are called artificial magnets.
(Eg.) bar-magnets, horseshoe magnets.
Man-made magnets are called artificial magnets.
(Eg.) bar-magnets, horseshoe magnets.
Bar-magnet, Horseshoe magnet, Ring magnet and Needle magnet are generally used artificial magnets.
Oval-shape, Disc shape and cylindrical shape magnets are also available.
Bar-magnet, Horseshoe magnet, Ring magnet and Needle magnet are generally used artificial magnets.
Oval-shape, Disc shape and cylindrical shape magnets are also available.
Substances which are attracted by magnets are called magnetic substances. (Eg.) Iron, Cobolt, Nickel
Substances which are attracted by magnets are called magnetic substances. (Eg.) Iron, Cobolt, Nickel
Substances which are not attracted by magnets are called non-magnetic substances. (Eg.) Paper, Plastic etc.
Substances which are not attracted by magnets are called non-magnetic substances. (Eg.) Paper, Plastic etc.