Advertisements
Advertisements
प्रश्न
Can we have a single north pole, or a single south pole?
उत्तर
No, we cannot have a single north or south pole. Magnetic poles are always found in pairs. They are equal in strength and opposite in nature. Even if we break a magnet into a number of pieces, each piece will become a magnet with equal and opposite poles.
APPEARS IN
संबंधित प्रश्न
State two advantages of an electromagnet over a permanent magnet.
A tangent galvanometer is connected directly to an ideal battery. If the number of turns in the coil is doubled the deflection will
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
Two long bare magnets are placed with their axes coinciding in such a way that the north pole of the first magnet is 2.0 cm from the south pole of the second. If both the magnets have a pole strength of 10 Am, find the force exerted by one magnet of the other.
Figure shows some of the equipotential surfaces of the magnetic scalar potential. Find the magnetic field B at a point in the region.
The magnetic field at a point, 10 cm away from a magnetic dipole, is found to be `2.0 xx 10^-4 "T"` . Find the magnetic moment of the dipole if the point is (a) in end-on position of the dipole and (b) in broadside-on position of the dipole.
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 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.
Why is it not possible to make permanent magnets from paramagnetic materials?
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?
Answer in brief.
Explain one application of electromagnet.
A thin diamagnetic rod is placed vertically between the poles of an electromagnet. When the current in the electromagnet is switched on, then the diamagnetic rod is pushed up, out of the horizontal magnetic field. Hence the rod gains gravitational potential energy. The work required to do this comes from ______.
Assertion: Electromagnetic are made of soft iron.
Reason: Coercivity of soft iron is small.
A steel wire of length 1 has a magnetic moment m it is then bent into a semicircular arc. The new magnetic moment is
Which of the following is most suitable for the core of an electromagnet?