CIE iGCSE Co-Ordinated Science P4.5.3 Magnetic effect of current Exam Style Questions Paper 2
▶️ Answer/Explanation
Reducing current decreases the magnetic field strength. Reversing current direction reverses the direction of the magnetic field (as given by the right-hand grip rule).
✅ Answer: (A)
✅ Answer: (A)
▶️ Answer/Explanation
The magnetic field around a straight current-carrying wire forms concentric circles centred on the wire.
Using the right-hand grip rule, with the current coming out of the page, the field circles counterclockwise around the wire.
✅ Answer: (D)
Using the right-hand grip rule, with the current coming out of the page, the field circles counterclockwise around the wire.
✅ Answer: (D)
▶️ Answer/Explanation
Iron is used because it is easily magnetised when current flows and easily demagnetised when current stops, making it ideal for a temporary electromagnet.
Steel retains magnetism (used for permanent magnets), while aluminium and copper are not magnetic materials at all.
✅ Answer: (C)
Steel retains magnetism (used for permanent magnets), while aluminium and copper are not magnetic materials at all.
✅ Answer: (C)
▶️ Answer/Explanation
A current-carrying solenoid produces a magnetic field pattern very similar to that of a bar magnet, with field lines emerging from one end (north pole) and curving round to enter the other end (south pole).
Inside the solenoid, the field lines run parallel to the axis and are evenly spaced, showing a strong, uniform field.
Only one diagram correctly shows this bar-magnet-like pattern both inside and outside the coil.
✅ Answer: (D)
Inside the solenoid, the field lines run parallel to the axis and are evenly spaced, showing a strong, uniform field.
Only one diagram correctly shows this bar-magnet-like pattern both inside and outside the coil.
✅ Answer: (D)
▶️ Answer/Explanation
An electromagnet’s magnetism depends entirely on current flowing through its coil.
Switching the current on and off rapidly switches the magnetism on and off just as fast.
A permanent magnet’s magnetism cannot be switched off in this way.
✅ Answer: (A)
Switching the current on and off rapidly switches the magnetism on and off just as fast.
A permanent magnet’s magnetism cannot be switched off in this way.
✅ Answer: (A)