PAF Physics MCQs

By: Prof. Dr. Fazal Rehman | Last updated: May 20, 2025

1. What is the principle force responsible for keeping an aircraft in the air?
(A) Thrust
(B) Drag
(C) Lift
(D) Weight

2. The Mach number of an aircraft is the ratio of its speed to the speed of:
(A) Light
(B) Sound
(C) Wind
(D) Gravity

3. Which law explains the reaction force produced when an aircraft engine expels gases backward?
(A) Newton’s First Law
(B) Newton’s Second Law
(C) Newton’s Third Law
(D) Bernoulli’s Principle

4. What happens to air pressure as altitude increases?
(A) Increases
(B) Decreases
(C) Remains the same
(D) Fluctuates

5. Which of the following is NOT a type of drag acting on an aircraft?
(A) Induced drag
(B) Parasite drag
(C) Wave drag
(D) Gravitational drag

6. The lift generated by a wing is primarily due to:
(A) Increased pressure above the wing
(B) Decreased pressure below the wing
(C) Pressure difference between lower and upper surfaces
(D) Frictional force of air

7. Which instrument is used to measure the altitude of an aircraft?
(A) Altimeter
(B) Speedometer
(C) Gyroscope
(D) Accelerometer

8. The rate of change of velocity of an aircraft is known as:
(A) Speed
(B) Displacement
(C) Acceleration
(D) Momentum

9. Which physical quantity is conserved during the flight of an aircraft?
(A) Energy
(B) Momentum
(C) Mass
(D) All of the above

10. The aerodynamic center of a wing is the point where:
(A) Lift acts
(B) Drag is minimum
(C) Moment about the point is constant with angle of attack
(D) Thrust is maximum