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प्रश्न
Answer in brief.
Explain one application of electromagnet.
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उत्तर
Electromagnets are used for various purposes on a day to day basis. For example, electromagnets are used in the large cranes which are used in waste yards. Electromagnets are also widely used in numerous electromechanical and electronic devices. Some of the common uses are given below.
- Uses in Home Appliances: Most of the electric appliances used in the home use electromagnetism as the basic working principle. Some electromagnet uses in the home include the electric fan, electric doorbell, induction cooker, magnetic locks, etc. In an electric fan, the electromagnetic induction keeps the motor rotating on and on making the blade of the fan to rotate. Also in an electric doorbell when the button is pressed, due to the electromagnetic forces the coil gets energized and the bell sounds.
- Uses in Medical Field: The uses of electromagnets are also seen in the medical field. MRI scan which is short for Magnetic Resonance Imaging is a device that uses electromagnets. The device can scan all the tiny details in the human body with the help of electromagnetism.
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Uses in Memory Storage Devices and Computer Hardware: The data in ebook gadgets and phones are stored in the electromagnetic format in the form of bytes and bits. The computer hardware is also having a magnetic tape which works on the principle of electromagnetism. Even in the olden days’ electromagnets had a huge role in the data storage of VCP and VCR.
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संबंधित प्रश्न
State any two advantages of electromagnets over permanent magnets.
State two advantages of an electromagnet over a permanent magnet.
Why is the core of an electromagnet made of ferromagnetic materials?
Can we have a single north pole, or a single south pole?
The force on a north pole, `vecF = mvecB` , parallel to the field `vecB` . Does it contradict our earlier knowledge that a magnetic field can exert forces only perpendicular to itself?
A dip circle is taken to geomagnetic equator. The needle is allowed to move in a vertical plane perpendicular to the magnetic meridian. The needle will stay ______.
A tangent galvanometer is connected directly to an ideal battery. If the number of turns in the coil is doubled the deflection will
Consider the situation of the previous problem. The directions of the magnetic field due to the dipole are opposite at
(a) P1 and P2
(b) Q1 and Q2
(c) P1 and Q1
(d) P2 and Q2
To measure the magnetic moment of a bar magnet, one may use
(a) a tangent galvanometer
(b) a deflection galvanometer if the earth's horizontal field is known
(c) an oscillation magnetometer if the earth's horizontal field is known
(d) both deflection and oscillation magnetometer if the earth's horizontal field is not known
A uniform magnetic field of `0.20 xx 10^-3 "T"` exists in the space. Find the change in the magnetic scalar potential as one moves through 50 cm along the field.
A bar magnet has a length of 8 cm. The magnetic field at a point at a distance 3 cm from the centre in the broadside-on position is found to be `4 xx 10^-6 "T"`.Find the pole strength of the magnet.
A magnetic dipole of magnetic moment `1.44 "A m"^2`is placed horizontally with the north pole pointing towards north. Find the position of the neutral point if the horizontal component of the earth's magnetic field is 18 μT.
If the earth's magnetic field has a magnitude 3.4 × 10−5 T at the magnetic equator of the earth, what would be its value at the earth's geomagnetic poles?
A magnetic needle is free to rotate in a vertical plane which makes an angle of 60° with the magnetic meridian. If the needle stays in a direction making an angle of `tan^-1(2sqrt(3))` with the horizontal, what would be the dip at that place?
A deflection magnetometer is placed with its arms in north-south direction. How and where should a short magnet having M/BH = 40 A m2 T−1 be placed so that the needle can stay in any position?
The combination of two bar magnets makes 10 oscillations per second in an oscillation magnetometer when like poles are tied together and 2 oscillations per second when unlike poles are tied together. Find the ratio of the magnetic moments of the magnets. Neglect any induced magnetism.
A short magnet oscillates in an oscillation magnetometer with a time period of 0.10 s where the earth's horizontal magnetic field is 24 μT. A downward current of 18 A is established in a vertical wire placed 20 cm east of the magnet. Find the new time period.
A short magnet makes 40 oscillations per minute when used in an oscillation magnetometer at a place where the earth's horizontal magnetic field is 25 μT. Another short magnet of magnetic moment 1.6 A m2 is placed 20 cm east of the oscillating magnet. Find the new frequency of oscillation if the magnet has its north pole (a) towards north and (b) towards south.
Soft iron is used to make the core of the transformer because of its ______.
Which property of soft iron makes it useful for preparing electromagnet?
What should be retentivity and coercivity of permanent magnet?
