Physics chapter 20 important Mcqs for Fsc Students

 📘 Physics Chapter 20 – MCQs

Q1: Unit of magnetic flux is?

A) Tesla

B) Weber ✅

C) Volt

D) Ampere

Q2: Transformer works on?

A) Ohm’s law

B) Faraday’s law ✅

C) Newton’s law

D) Coulomb’s law

Q3: AC current changes?

A) Magnitude

B) Direction

C) Both ✅

D) None

Q4: Generator converts?

A) Electrical → Mechanical

B) Mechanical → Electrical ✅

C) Heat → Electrical

D) Light → Electrical

Q5: Lenz’s law is related to?

A) Direction of current ✅

B) Voltage

C) Resistance

D) Power

Q6: Step-up transformer increases?

A) Current

B) Voltage ✅

C) Resistance

D) Power

Q7: Magnetic flux depends on?

A) Area

B) Magnetic field

C) Angle

D) All ✅

Q8: DC current flows in?

A) Both directions

B) One direction ✅

C) Circular 🔢 Numericals (Simple Type)

❓ Q1:

Magnetic flux = 0.02 Wb, time = 0.01 s

Find induced EMF

Ans:

EMF = Φ / t

= 0.02 / 0.01

= 2 V

❓ Q2:

Primary turns = 100, Secondary = 200

Input voltage = 10V

Find output voltage

Ans:

Vs/Vp = Ns/Np

Vs/10 = 200/100

Vs = 20V

D) None