Physics for Engineers

Question 1

1. Quantity with both magnitude and direction is ___.
   A. Scalar B. Vector C. Distance D. Speed

Answer 1

✅ Answer: B – Vector
Example force, velocity — need magnitude and direction.

Question 2

2. Unit of Force in SI system is ___.
   A. Dyne B. Erg C. Newton D. Joule

Answer 2

✅ Answer: C – Newton
1 N = 1 kg·m/s² (from F = ma).

Question 3

3. Work = ___.
   A. Force + Distance B. Force / Distance C. Force × Distance cos θ D. Mass × Velocity

Answer 3

✅ Answer: C – Force × Distance cos θ
Component of force along displacement.

Question 4

4. Power is defined as ___.
   A. Work × Time B. Work / Time C. Force × Velocity D. Energy / Mass

Answer 4

✅ Answer: B – Work / Time
Rate of doing work (W/t).

Question 5

5. Kinetic energy = ___.
   A. ½ mv B. ½ mv² C. mgh D. mgh²

Answer 5

✅ Answer: B – ½ mv²
Energy due to motion.

Question 6

6. Potential energy = ___.
   A. ½ mv² B. mgh C. mgv D. F × v

Answer 6

✅ Answer: B – mgh
Energy by position in gravitational field.

Question 7

7. Unit of Work is ___.
   A. Joule B. Watt C. Newton D. Erg

Answer 7

✅ Answer: A – Joule
1 J = 1 N·m.

Question 8

8. Newton’s Second Law states ___.
   A. F = ma B. For every action… C. Object remains at rest D. F = W/t

Answer 8

✅ Answer: A – F = ma
Acceleration ∝ net force.

Question 9

9. Momentum p = ___.
   A. m/v B. m × v C. v/m D. mv²

Answer 9

✅ Answer: B – m × v
Product of mass and velocity.

Question 10

10. Impulse is equal to ___.
    A. Change in velocity B. Change in momentum C. Force × distance D. Power × time

Answer 10

✅ Answer: B – Change in momentum
Impulse = F Δt = Δp.

Question 11

11. 1 horsepower ≈ ___.
    A. 550 J/s B. 746 W C. 1 kW D. 500 W

Answer 11

✅ Answer: B – 746 W
Mechanical horsepower conversion.

Question 12

12. Unit of pressure in SI is ___.
    A. atm B. bar C. Pascal D. torr

Answer 12

✅ Answer: C – Pascal (Pa = N/m²).
Named after Blaise Pascal.

Question 13

13. Archimedes’ principle states: ___.
    A. F = ma B. Buoyant force = weight of displaced fluid C. Equal and opposite reaction D. P₁V₁ = P₂V₂

Answer 13

✅ Answer: B – Buoyant force = weight of displaced fluid.
Explains why objects float.

Question 14

14. Density = ___.
    A. Weight/Volume B. Mass/Volume C. Volume/Mass D. Force/Area

Answer 14

✅ Answer: B – Mass/Volume
ρ = m/V.

Question 15

15. Unit of Power = ___.
    A. Watt B. Joule C. Newton D. Volt

Answer 15

✅ Answer: A – Watt
1 W = 1 J/s.

Question 16

16. 1 kilowatt-hour (kWh) = ___.
    A. 1000 J B. 3600 J C. 3.6 × 10⁶ J D. 3600 W

Answer 16

✅ Answer: C – 3.6 × 10⁶ J
Power × time = 1000 W × 3600 s.

Question 17

17. Ohm’s Law: ___.
    A. V = IR B. P = VI C. I = V/R² D. V = I/R

Answer 17

✅ Answer: A – V = IR
Voltage directly proportional to current.

Question 18

18. Unit of electric charge = ___.
    A. Ampere B. Coulomb C. Volt D. Farad

Answer 18

✅ Answer: B – Coulomb
1 C = 1 A·s.

Question 19

19. Unit of electric potential = ___.
    A. Ampere B. Joule C. Volt D. Ohm

Answer 19

✅ Answer: C – Volt
1 V = 1 J/C.

Question 20

20. Unit of capacitance = ___.
    A. Ohm B. Farad C. Henry D. Weber

Answer 20

✅ Answer: B – Farad
F = C/V (capacitor ability to store charge).

Question 21

21. Magnetic flux density unit = ___.
    A. Tesla B. Weber C. Coulomb D. Newton

Answer 21

✅ Answer: A – Tesla
1 T = 1 Wb/m².

Question 22

22. Transformer works on the principle of ___.
    A. Electrostatics B. Electromagnetic induction C. Ohm’s law D. Thermodynamics

Answer 22

✅ Answer: B – Electromagnetic induction
Changing flux induces emf.

Question 23

23. Heat transfer by direct contact is called ___.
    A. Conduction B. Convection C. Radiation D. Evaporation

Answer 23

✅ Answer: A – Conduction
Particles collide to transfer energy.

Question 24

24. Speed of light in vacuum ≈ ___.
    A. 3 × 10⁶ m/s B. 3 × 10⁸ m/s C. 3 × 10⁵ km/s D. Both B and C

Answer 24

✅ Answer: D – Both B and C
Equivalent forms (3 × 10⁸ m/s = 3 × 10⁵ km/s).

Question 25

25. 1 atmosphere pressure = ___. A. 101.3 kPa B. 100 Pa C. 1 bar D. 760 mmHg

Answer 25

✅ Answer: A – 101.3 kPa (also ≈ 760 mmHg) Standard atmospheric pressure.