Magnetism — Set 1
Physics · चुंबकत्व · Questions 1–10 of 50
Which statement about magnetic poles is correct?
Correct Answer: D. Like poles repel each other.
Like poles repel, so the marked statement is correct. Unlike poles attract each other in ordinary magnets. A bar magnet always has two poles, north and south.
What is the SI unit of magnetic flux density (B)?
Correct Answer: C. Tesla
Magnetic flux density is measured in tesla in SI units. It describes how strong the magnetic field is in a region. A larger tesla value means a stronger field.
Outside a bar magnet, magnetic field lines generally go from?
Correct Answer: D. North pole to south pole
Outside a magnet, field lines are taken to emerge from the north pole and enter the south pole. This direction matches the way a compass north end points. Inside the magnet, the lines return from south to north.
A compass needle placed near a magnet aligns mainly because it?
Correct Answer: A. Experiences torque due to a magnetic field
A compass needle is a small magnet, so a magnetic field exerts a torque on it. The needle rotates until it aligns with the local magnetic field direction. The north-seeking end points along the field lines.
Which statement about Earth and magnetism is generally correct?
Correct Answer: A. Earth behaves like a giant magnet.
Earth has a magnetic field and behaves like a giant magnet. The field helps guide compass needles for navigation. It also helps deflect many charged particles from space.
Magnetic declination is the angle between?
Correct Answer: C. Geographic meridian and magnetic meridian
Declination is the angle between the geographic meridian and the magnetic meridian. It tells how much a compass direction differs from true north. Declination varies with location and time.
Angle of dip (inclination) is the angle between Earth’s magnetic field and the?
Correct Answer: A. Horizontal plane
Angle of dip is measured between the Earth's magnetic field direction and the horizontal plane. It shows how much the field tilts downward into Earth. Dip changes from 0° near the magnetic equator to 90° near the magnetic poles.
A neutral point near a magnet is a point where?
Correct Answer: D. Resultant magnetic field is zero
A neutral point is where the net magnetic field becomes zero. It occurs when two magnetic fields cancel each other. A compass placed there shows no preferred direction.
Magnetic permeability mainly tells how easily a material?
Correct Answer: B. Allows magnetic field to pass through it
Permeability measures how well a material supports magnetic field formation inside it. Higher permeability generally means the material is more easily magnetized. Soft iron has high permeability compared to air.
Diamagnetic materials are generally?
Correct Answer: D. Weakly repelled by a magnet
Diamagnetic materials are weakly repelled by magnetic fields, so the marked option is correct. Their induced magnetism opposes the applied field direction. Many common substances show diamagnetism to a small extent.