Basic Qualification · B-005 Basic electronics and theory · B-005-006-007
Laquelle de ces combinaisons de résistances pourrait servir de charge fictive de 50 ohms et tolérer 5 watts?
- AQuatre résistances 200 ohms 2 watts en parallèle
- BDeux résistances 100 ohms 5 watts en série
- CDeux résistances 25 ohms 2 watts en série
- DDix résistances 500 ohms 0,25 watt en parallèle
Correct answer: A — Quatre résistances 200 ohms 2 watts en parallèle. Question tirée de la banque officielle d'ISDE.
Why
Four 2-watt 200-ohm resistors in parallel work because connecting four identical resistors this way divides the total resistance by four, giving exactly 50 ohms, while the power rating adds up to eight watts, which safely exceeds the required five watts. The full explanation — and one for every question — is in Pro.
Practise this section
Basic electronics and theory is section B-005 of the Basic exam: The theory: Ohm's law, power, series and parallel circuits, AC and DC, frequency and wavelength, decibels, and the metric prefixes the exam leans on.
Drill B-005 — free, no account