MDCAT Physics — Alternating Current
Alternating Current is a core Physics topic in the PMDC MDCAT syllabus, covering 4 subtopics. Below are the subtopics to revise, how often the topic appears in past papers, and real past-paper MCQs to try.
Subtopics (4)
- AC Through Capacitor
- AC Through Inductor
- Phase of Alternating Current
- Resonance (RLC Circuits)
How Alternating Current is tested
Across the 16 MDCAT past papers on ParhaiKrlo, Alternating Current accounts for 9 questions. It appears in 7 of them, about 1.3 questions a paper. The heaviest was MDCAT 2009, with 2 questions, and the most recent is MDCAT 2025, with 1.
| Paper | Questions |
|---|---|
| MDCAT 2025 | 1 |
| MDCAT 2024 | 1 |
| MDCAT 2019 | 1 |
| MDCAT 2017 | 1 |
| MDCAT 2013 | 1 |
| MDCAT 2009 | 2 |
| MDCAT 2008 | 2 |
Alternating Current MCQs from the MDCAT past papers
Try each one before opening the answer. Each comes with a short explanation.
- Q1 · MDCAT 2025 · Alternating Current
A phase difference of 90° is equal to:
- A.π radians
- B.π/2 radians
- C.2π radians
- D.π/4 radians
Show answer
Answer: B. π/2 radians — A 90° phase difference equals π/2 radians.
- Q2 · MDCAT 2024 · Alternating Current
In an AC generator the emf will be maximum when factor sinωt is equal to
- A.Zero
- B.1
- C.2
- D.1/2
Show answer
Answer: B. 1 — AC generator EMF is maximum when sin(ωt) = 1.
- Q3 · MDCAT 2019 · Alternating Current
An alternation voltage V (in volts) is represented by the equation: V = 300 sin (100πt). What is the value of "f" for this voltage?
- A.25 Hz
- B.200 Hz
- C.50 Hz
- D.100 Hz
Show answer
Answer: C. 50 Hz — Comparing V=300sin(100πt) to V=V0sin(2πft), 2πf=100π, so f=50 Hz.