CIE iGCSE Co-Ordinated Science P4.5.6 The transformer Exam Style Questions Paper 4
Question
(a) Fig. 12.1 shows a transformer.
(i) On Fig. 12.1, label the soft-iron core with an X.
▶️Answer/Explanation
The soft-iron core should be labeled with an X in the center of the transformer.
(ii) The transformer has 17 turns on the primary coil and 8 turns on the secondary coil. Calculate the output voltage when the a.c. power supply has an e.m.f. of 34,000 V.
Assume the transformer has an efficiency of 100%.
▶️Answer/Explanation
16,000 V
(b) Fig. 12.2 shows a current-carrying solenoid.
On Fig. 12.2, draw the magnetic field pattern, including direction, around the solenoid.
▶️Answer/Explanation
Draw parallel field lines inside the solenoid with arrows pointing from north to south pole, and curved field lines outside.
(c) The radioactive isotope uranium-238 decays into an isotope of thorium by emitting an α-particle.
(i) Use the correct nuclide notation to complete the decay equation for uranium-238.
▶️Answer/Explanation
²³⁸₉₂U → ²³⁴₉₀Th + ⁴₂α
(ii) Suggest why an α-particle is deflected when moving through a magnetic field.
▶️Answer/Explanation
Because it is a charged particle (positive charge) and moving charges experience force in magnetic fields.