Physics
Which method of making magnets involves the use of two magnets?
- Single touch method
- Double touch method
- Magnetic induction
- Electrical method
Answer
Double touch method
Reason — In the double touch method, two permanent magnets are used. Their opposite poles are touched simultaneously at the ends of the iron bar and moved towards the center, aligning the molecules and magnetising the bar. Single touch, magnetic induction and electrical method use only single magnet to magnetise.
Related Questions
Fill in the blanks.
(a) …………… magnets are weak and …………… magnets are strong.
(b) …………… is a true test for magnetism.
(c) Magnets that retain their magnetism for a short period of time are called …………… magnets.
(d) During demagnetisation, the …………… of the molecules of the magnet leads to loss of magnetism.
(e) The soft iron strips that are used in storage of magnets are called …………… .
State whether the following statements are true or false. Correct the false statements.
(a) Both the poles of the magnet exist in pairs.
(b) The strength of the magnetic field of a magnet increases as we move away from it.
(c) Magnetic lines of force may intersect one another.
(d) Magnetic induction is a temporary method of making magnets.
(e) The magnet remains unaffected even if handled roughly.
Which of the following is an example of permanent magnets?
- Door of the refrigerator
- Door bell
- Generators
- Electric cranes
Which of the following is made when electricity is passed through it?
- Lodestone
- Natural magnet
- Permanent magnet
- Electromagnet