Advertisements
Advertisements
Question
Answer in brief.
Explain one application of electromagnet.
Advertisements
Solution
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.
-
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.
APPEARS IN
RELATED QUESTIONS
State two advantages of an electromagnet over a permanent magnet.
Why is the core of an electromagnet made of ferromagnetic materials?
Why should the material used for making permanent magnets have high coercivity?
Can we have a single north pole, or a single south pole?
Compare the direction of the magnetic field inside a solenoid with that of the field there if the solenoid is replaced by its equivalent combination of north pole and south pole.
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 ______.
Which of the following four graphs may best represent the current-deflection relation in a tangent galvanometer?
If the current is doubled, the deflection is also doubled in
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
Show that the magnetic field at a point due to a magnetic dipole is perpendicular to the magnetic axis if the line joining the point with the centre of the dipole makes an angle of `tan^-1(sqrt 2)` with the magnetic axis
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.
The desirable properties for making permanent magnets are _________________ .
The coercive force for a certain permanent magnet is 4.0 × 104 A m−1. This magnet is placed inside a long solenoid of 40 turns/cm and a current is passed in the solenoid to demagnetise it completely. Find the current.
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 moving-coil galvanometer has a 50-turn coil of size 2 cm × 2 cm. It is suspended between the magnetic poles producing a magnetic field of 0.5 T. Find the torque on the coil due to the magnetic field when a current of 20 mA passes through it.
The magnetometer of the previous problem is used with the same magnet in Tan-B position. Where should the magnet be placed to produce a 37° deflection of the needle?
A bar magnet takes π/10 second the complete one oscillation in an oscillation magnetometer. The moment of inertia of the magnet about the axis of rotation is 1.2 × 10−4 kg m2 and the earth's horizontal magnetic field is 30 μT. Find the magnetic moment of the magnet.
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?
The relation b/w magnetic susceptibility xm and relativ~ permeability µr is
A steel wire of length 1 has a magnetic moment m it is then bent into a semicircular arc. The new magnetic moment is
