PYQ-Based | Polytechnic | Semester 1 & 2
1. The atomic number of an element is determined by:
a) Number of neutrons
b) Number of electrons
c) Number of protons
d) Sum of protons and neutrons
View Answer
c) Number of protons
Explanation: Atomic number (Z) is the number of protons in the nucleus, which defines the identity of the element.
2. The SI unit of force is:
a) Joule
b) Watt
c) Newton
d) Pascal
View Answer
c) Newton
Explanation: Force = mass × acceleration, so the unit is kg·m/s², which is defined as 1 Newton (N).
3. In simple harmonic motion, the restoring force is proportional to:
a) Velocity
b) Acceleration
c) Displacement
d) Time
View Answer
c) Displacement
Explanation: Hooke’s law states F = -kx, where displacement (x) is directly proportional to the restoring force.
4. The speed of light in vacuum is approximately:
a) 3 × 10⁶ m/s
b) 3 × 10⁸ m/s
c) 3 × 10¹⁰ m/s
d) 3 × 10¹² m/s
View Answer
b) 3 × 10⁸ m/s
Explanation: The standard value of speed of light in vacuum (c) is 299,792,458 m/s ≈ 3 × 10⁸ m/s.
5. Which of the following is a vector quantity?
a) Mass
b) Temperature
c) Velocity
d) Energy
View Answer
c) Velocity
Explanation: Velocity has both magnitude and direction, making it a vector; others are scalars.
6. The law of conservation of energy states that energy:
a) Can be created
b) Can be destroyed
c) Cannot be created or destroyed
d) Increases with time
View Answer
c) Cannot be created or destroyed
Explanation: Energy can only be transformed from one form to another; total energy remains constant.
7. The boiling point of water at standard pressure is:
a) 0°C
b) 100°C
c) 212°C
d) 373°C
View Answer
b) 100°C
Explanation: Water boils at 100°C (373 K) at 1 atm pressure; 212°F is the Fahrenheit equivalent.
8. Ohm’s law is expressed as:
a) V = IR
b) P = VI
c) I = VR
d) R = VI
View Answer
a) V = IR
Explanation: Voltage (V) = Current (I) × Resistance (R); fundamental relation in DC circuits.
9. The primary source of energy for Earth’s climate system is:
a) Geothermal energy
b) Tidal energy
c) Solar radiation
d) Nuclear fusion in Earth’s core
View Answer
c) Solar radiation
Explanation: The Sun provides nearly all the energy driving weather, oceans, and photosynthesis.
10. The dimensional formula for pressure is:
a) [ML⁻¹T⁻²]
b) [MLT⁻²]
c) [ML⁻¹T⁻¹]
d) [M⁰L⁰T⁰]
View Answer
a) [ML⁻¹T⁻²]
Explanation: Pressure = Force/Area = (MLT⁻²)/L² = ML⁻¹T⁻².
11. The unit of electric charge in SI system is:
a) Volt
b) Ampere
c) Coulomb
d) Ohm
View Answer
c) Coulomb
Explanation: Charge (Q) = Current (I) × Time (t), so unit is ampere-second = coulomb.
12. The angle of reflection is equal to the angle of incidence according to:
a) Law of refraction
b) Law of reflection
c) Snell’s law
d) Newton’s law
View Answer
b) Law of reflection
Explanation: First law of reflection: angle of incidence = angle of reflection.
13. The work done by a force is zero when the force is:
a) Parallel to displacement
b) Perpendicular to displacement
c) Opposite to displacement
d) At 45° to displacement
View Answer
b) Perpendicular to displacement
Explanation: Work = F·s·cosθ; when θ = 90°, cos90° = 0, so work = 0.
14. The mass number of an atom is the sum of:
a) Protons and electrons
b) Neutrons and electrons
c) Protons and neutrons
d) Only neutrons
View Answer
c) Protons and neutrons
Explanation: Mass number (A) = number of protons (Z) + number of neutrons (N).
15. The frequency of a wave is measured in:
a) Meter
b) Second
c) Hertz
d) Joule
View Answer
c) Hertz
Explanation: Frequency (f) = 1/T, unit is s⁻¹ = hertz (Hz).
16. The kinetic energy of a body is proportional to:
a) Its mass
b) Square of its velocity
c) Its acceleration
d) Time
View Answer
b) Square of its velocity
Explanation: KE = ½mv², so KE ∝ v².
17. The focal length of a plane mirror is:
a) Zero
b) Infinity
c) Positive
d) Negative
View Answer
b) Infinity
Explanation: Plane mirror forms virtual image at infinity focal length (f = ∞).
18. The unit of power is:
a) Joule
b) Newton
c) Watt
d) Pascal
View Answer
c) Watt
Explanation: Power = Work/Time, unit = J/s = watt (W).
19. The specific heat capacity of water is:
a) 4200 J/kg·K
b) 2100 J/kg·K
c) 900 J/kg·K
d) 460 J/kg·K
View Answer
a) 4200 J/kg·K
Explanation: Water has high specific heat: 4200 J/kg·K (or 1 cal/g·°C).
20. The refractive index of a medium is the ratio of speed of light in:
a) Vacuum to medium
b) Medium to vacuum
c) Air to medium
d) Medium to air
View Answer
a) Vacuum to medium
Explanation: n = c/v, where c is speed in vacuum, v in medium.
21. The escape velocity from Earth’s surface is approximately:
a) 7.9 km/s
b) 11.2 km/s
c) 25 km/s
d) 3 km/s
View Answer
b) 11.2 km/s
Explanation: v_escape = √(2GM/R) ≈ 11.2 km/s for Earth.
22. The magnetic field inside a long solenoid depends on:
a) Current and number of turns per unit length
b) Radius of solenoid
c) Length of solenoid
d) Material of core
View Answer
a) Current and number of turns per unit length
Explanation: B = μ₀nI, where n = turns per unit length, I = current.
23. The unit of momentum is:
a) kg·m/s
b) kg·m/s²
c) N·s
d) Both a and c
View Answer
d) Both a and c
Explanation: Momentum = mv, unit kg·m/s = N·s.
24. The process of splitting of white light into seven colors is called:
a) Reflection
b) Refraction
c) Dispersion
d) Diffraction
View Answer
c) Dispersion
Explanation: Different wavelengths refract by different amounts in a prism.
25. The half-life of a radioactive element is the time taken for:
a) All atoms to decay
b) Half the atoms to decay
c) Activity to become zero
d) One atom to decay
View Answer
b) Half the atoms to decay
Explanation: T½ is time for number of nuclei to reduce to half.
26. The unit of wavelength is:
a) Second
b) Hertz
c) Meter
d) Joule
View Answer
c) Meter
Explanation: Wavelength (λ) is distance, so unit is meter (m).
27. The acceleration due to gravity on the moon is about:
a) 1/6th of Earth
b) 1/2 of Earth
c) Same as Earth
d) 6 times Earth
View Answer
a) 1/6th of Earth
Explanation: g_moon ≈ 1.6 m/s², g_earth ≈ 9.8 m/s², so g_moon ≈ g_earth/6.
28. The SI unit of intensity of sound is:
a) Hertz
b) Decibel
c) Watt/m²
d) Pascal
View Answer
c) Watt/m²
Explanation: Intensity = power/area, unit W/m²; decibel is logarithmic scale.
29. The potential energy of a body at height h is:
a) mgh
b) ½mv²
c) Fd
d) mv
View Answer
a) mgh
Explanation: Gravitational PE = mgh, where h is height above reference.
30. The critical angle is the angle of incidence in denser medium when angle of refraction is:
a) 0°
b) 90°
c) 180°
d) 45°
View Answer
b) 90°
Explanation: sin i_c = 1/μ; when i = i_c, r = 90°.
31. The image formed by a convex lens when object is at focus is:
a) Real, inverted, magnified
b) Virtual, erect, magnified
c) At infinity
d) At focus
View Answer
c) At infinity
Explanation: When u = -f, image is at infinity (parallel rays).
32. The resistance of a wire is inversely proportional to:
a) Length
b) Area of cross-section
c) Temperature
d) Material
View Answer
b) Area of cross-section
Explanation: R = ρl/A, so R ∝ 1/A.
33. The direction of induced emf is given by:
a) Fleming’s left-hand rule
b) Fleming’s right-hand rule
c) Right-hand thumb rule
d) Coulomb’s law
View Answer
b) Fleming’s right-hand rule
Explanation: For generators, induced emf direction by right-hand rule.
34. The latent heat of vaporization is used during:
a) Melting
b) Boiling
c) Freezing
d) Condensation
View Answer
b) Boiling
Explanation: Energy to change liquid to vapor at constant temperature.
35. The weight of a body is maximum at:
a) Poles
b) Equator
c) Center of Earth
d) Moon
View Answer
a) Poles
Explanation: g is maximum at poles due to flattening of Earth and no centrifugal effect.
36. The speed of sound in air at 0°C is approximately:
a) 332 m/s
b) 340 m/s
c) 400 m/s
d) 300 m/s
View Answer
a) 332 m/s
Explanation: Standard value at 0°C is 331–332 m/s.
37. The capacitance of a parallel plate capacitor increases with:
a) Increase in distance between plates
b) Decrease in area of plates
c) Increase in area of plates
d) Decrease in dielectric constant
View Answer
c) Increase in area of plates
Explanation: C = ε₀A/d, so C ∝ A.
38. The unit of electric field intensity is:
a) N/C
b) V/m
c) Both a and b
d) J/C
View Answer
c) Both a and b
Explanation: E = F/q = N/C; also E = V/d = V/m.
39. The phenomenon of total internal reflection occurs when light travels from:
a) Rarer to denser medium
b) Denser to rarer medium
c) Same medium
d) Vacuum to air
View Answer
b) Denser to rarer medium
Explanation: Required for i > i_c, only possible from denser to rarer.
40. The power of a lens is measured in:
a) Meter
b) Dioptre
c) Watt
d) Joule
View Answer
b) Dioptre
Explanation: P = 1/f (f in meter), unit is dioptre (D).
41. The direction of magnetic field due to a straight current-carrying conductor is given by:
a) Right-hand thumb rule
b) Left-hand rule
c) Fleming’s rule
d) Coulomb’s rule
View Answer
a) Right-hand thumb rule
Explanation: Thumb in current direction, fingers curl in field direction.
42. The energy stored in a capacitor is:
a) ½CV²
b) CV
c) ½C/V
d) QV
View Answer
a) ½CV²
Explanation: Energy = ½QV = ½CV² = Q²/(2C).
43. The unit of thermal conductivity is:
a) W/m·K
b) J/kg·K
c) J/s
d) cal/cm·s·°C
View Answer
a) W/m·K
Explanation: k = Qd/(AΔT t), unit W/m·K.
44. The Doppler effect is observed in:
a) Light waves
b) Sound waves
c) Both a and b
d) Only water waves
View Answer
c) Both a and b
Explanation: Change in frequency due to relative motion of source and observer.
45. The number of images formed by two plane mirrors at 60° is:
a) 3
b) 5
c) 6
d) Infinite
View Answer
b) 5
Explanation: n = 360°/θ - 1 = 360/60 - 1 = 5.
46. The SI unit of luminous intensity is:
a) Lux
b) Lumen
c) Candela
d) Watt
View Answer
c) Candela
Explanation: Candela (cd) is the base unit of luminous intensity.
47. The time period of a simple pendulum depends on:
a) Mass of bob
b) Amplitude
c) Length of string
d) Color of bob
View Answer
c) Length of string
Explanation: T = 2π√(l/g), independent of mass and small amplitude.
48. The transformer works on the principle of:
a) Electromagnetic induction
b) Electrostatic induction
c) Thermoelectric effect
d) Photoelectric effect
View Answer
a) Electromagnetic induction
Explanation: Changing magnetic flux induces emf in secondary coil.
49. The nuclear force is:
a) Long-range
b) Weak
c) Short-range
d) Repulsive
View Answer
c) Short-range
Explanation: Strong nuclear force acts only within ~10⁻¹⁵ m (nuclear size).
50. The dimensional formula for impulse is:
a) [MLT⁻¹]
b) [MLT⁻²]
c) [ML²T⁻²]
d) [MLT]
View Answer
a) [MLT⁻¹]
Explanation: Impulse = change in momentum = mΔv = [MLT⁻¹].
Read also 1st Year Diploma in Physics MSBTE PYQs MCQs
1st Year Diploma in Physics MCQs
1st Year Diploma in Chemistry PYQs MCQs
1st Year Diploma in Chemistry MCQs
1st Year Diploma in Chemistry MSBTE PYQs MCQs
Diploma in Chemical Engineering PYQs MCQs