Q1. Which of the following correctly describes where a magnetic field exists?
Multiple Choice · 1 point
- · Only inside permanent magnets
- · Around permanent magnets and moving electric charges
- · Only around stationary electric charges
- · Only in regions with no electric field
Q2. What does the spacing between magnetic field lines indicate?
Multiple Choice · 1 point
- · The temperature of the magnetic material
- · The type of magnetic pole nearest to that region
- · The direction of the magnetic field
- · The strength of the magnetic field
Q3. Which of the following is a correct property of magnetic field lines?
Multiple Choice · 1 point
- · They can cross one another at right angles
- · They travel from north to south inside the magnet
- · They always form closed loops
- · They only exist in the space outside a magnet
Q4. Which of the following is NOT a valid property of magnetic field lines?
Multiple Choice · 1 point
- · They never intersect one another
- · Their spacing indicates the relative field strength
- · They show the direction of force on a free north pole
- · They begin at north poles and terminate at south poles, just as electric field lines start and end on charges
Q5. When applying the right-hand grip rule to a straight current-carrying wire, the thumb points in the direction of:
Multiple Choice · 1 point
- · The magnetic field circling the wire
- · The conventional current in the wire
- · The direction of electron flow
- · The force experienced by the wire
Q6. A long straight wire carries conventional current flowing to the right. Using the right-hand grip rule, what is the direction of the magnetic field directly above the wire?
Multiple Choice · 1 point
- · Into the page
- · Out of the page
- · Upward
- · To the right
Q7. When the right-hand grip rule is applied to a solenoid with the fingers curling in the direction of conventional current, the thumb points toward:
Multiple Choice · 1 point
- · The south pole of the solenoid
- · The north pole of the solenoid
- · The geometric centre of the solenoid
- · The direction of electron flow
Q8. A stationary proton is placed in an otherwise empty region of space. Which fields does it produce?
Multiple Choice · 1 point
- · A magnetic field only
- · Both an electric field and a magnetic field
- · An electric field only
- · Neither an electric field nor a magnetic field
Q9. Which of the following correctly explains why a moving electric charge produces a magnetic field?
Multiple Choice · 1 point
- · Moving charges lose their electric field, which is converted into a magnetic field
- · A moving charge constitutes an electric current, which produces a magnetic field
- · Stationary charges also produce the same magnetic field, just weaker
- · Magnetic fields can only be produced by permanent magnets, not charges
Q10. Which of the following best describes the magnetic field inside a long solenoid carrying a steady current?
Multiple Choice · 1 point
- · Radial, pointing outward from the central axis
- · Approximately uniform and parallel to the axis
- · Concentric circles centred on each individual turn
- · Strongest at the centre and zero at the ends
Q11. What shape does the magnetic field form around a long straight current-carrying wire?
Multiple Choice · 1 point
- · Parallel lines along the wire
- · Radial lines pointing away from the wire
- · Concentric circles centred on the wire
- · Ellipses aligned with the current direction
Q12. A solenoid is wound such that, when viewed from the left end, the conventional current flows clockwise. What is the polarity of the left end?
Multiple Choice · 1 point
- · North pole
- · South pole
- · It has no defined polarity
- · It alternates between north and south
Q13. Which of the following changes would double the magnetic flux density inside a solenoid, assuming all other quantities remain constant?
Multiple Choice · 1 point
- · Doubling the length of the solenoid while keeping the total number of turns fixed
- · Doubling the current through the solenoid
- · Halving the total number of turns while keeping the length fixed
- · Doubling the cross-sectional area of the solenoid
Q14. Put the following descriptions in order, from the region of weakest to strongest magnetic field around a bar magnet.
Ordering · 2 points
- 1. Far from the magnet, well beyond the ends
- 2. Midway between the poles on the outside surface
- 3. Just outside one of the poles
- 4. At the surface of a pole face