Class 11 Physics - Chapter 1: Physical World & Measurement
MCQ 1 (JEE Main 2021)
A physical quantity that has different units in different measurement systems is:
🔘 a) Time
🔘 b) Mass
🔘 c) Force
🔘 d) Electric charge
✅ Answer: 🟢 (c) Force
Explanation:
(a) Time – Always measured in seconds in SI and CGS systems. ❌ Incorrect
(b) Mass – Always measured in kilograms (kg) in SI and grams (g) in CGS. ❌ Incorrect
(c) Force – Has different units in SI and CGS:
SI Unit: Newton (N)
CGS Unit: Dyne (1 N = 10⁵ Dynes)
🟢 Correct answer
(d) Electric Charge – Always measured in Coulombs (C) in SI and CGS. ❌ Incorrect
🔴 Important Points:
SI unit of Force = Newton (N).
CGS unit of Force = Dyne (1 N = 10⁵ Dyne).
Force is a vector quantity (it has both magnitude and direction).
Newton’s second law: F = ma.
Dyne is a much smaller unit than Newton.
MCQ 2 (NEET 2020)
Which of the following pairs have identical dimensions?
🔘 a) Work and Power
🔘 b) Energy and Torque
🔘 c) Force and Work
🔘 d) Impulse and Power
✅ Answer: 🟢 (b) Energy and Torque
Explanation:
(a) Work (ML²T⁻²) and Power (ML²T⁻³) – ❌ Different dimensions.
(b) Energy (ML²T⁻²) and Torque (ML²T⁻²) – 🟢 Identical dimensions.
(c) Force (MLT⁻²) and Work (ML²T⁻²) – ❌ Different dimensions.
(d) Impulse (MLT⁻¹) and Power (ML²T⁻³) – ❌ Different dimensions.
🟡 Important Points:
Torque (τ) = Force × Distance (ML²T⁻²).
Work (W) = Force × Displacement (ML²T⁻²).
🔴 SI unit of Energy & Torque = Joule (J) & Newton-meter (Nm).
Dimensional analysis helps in checking correctness of formulas.
Power (Work/Time) has different dimensions than Work.
MCQ 3 (JEE Advanced 2018)
A dimensionally correct equation is:
🔘 a) v = u + at
🔘 b) s = ut + ½ at²
🔘 c) E = mc²
🔘 d) All of the above
✅ Answer: 🟢 (d) All of the above
Explanation:
(a) v = u + at: Velocity (LT⁻¹) = (LT⁻¹) + (LT⁻² × T) → ✅ Correct.
(b) s = ut + ½ at²: Displacement (L) = (LT⁻¹ × T) + (LT⁻² × T²) → ✅ Correct.
(c) E = mc²: Energy (ML²T⁻²) = Mass (M) × (LT⁻¹)² → ✅ Correct.
(d) All of the above: 🟢 All three equations are dimensionally correct.
🟠 Important Points:
Dimensional consistency ensures equation correctness.
🔴 Power of units must match on both sides.
E = mc² explains energy-mass equivalence in relativity.
s = ut + ½ at² used in kinematics.
🔵 If an equation is dimensionally incorrect, it must be wrong.
MCQ 4 (CET 2019)
Which of the following has the same unit as angular velocity?
🔘 a) Frequency
🔘 b) Acceleration
🔘 c) Energy
🔘 d) Force
✅ Answer: 🟢 (a) Frequency
Explanation:
(a) Frequency: 🟢 Both have SI unit s⁻¹ (Hz for frequency, rad/s for angular velocity).
(b) Acceleration: m/s² (Different unit).
(c) Energy: Joule (Different unit).
(d) Force: Newton (Different unit).
🟡 Important Points:
Angular velocity (ω) = Change in angle / Time.
🔴 SI unit of angular velocity = rad/s.
Frequency (ν) = 1 / Time.
🟠 Frequency and angular velocity both measured in s⁻¹.
Rotational motion concepts use angular velocity & frequency.
I have continued adding more MCQs as per your format. Let me know if you need further modifications or additional MCQs. 🚀
Class 11 Physics - Chapter 1: Physical World & Measurement
MCQ 1 (JEE Main 2021)
A physical quantity that has different units in different measurement systems is:
🔘 a) Time
🔘 b) Mass
🔘 c) Force
🔘 d) Electric charge
✅ Answer: 🟢 (c) Force
Explanation:
(a) Time – Always measured in seconds in SI and CGS systems. ❌ Incorrect
(b) Mass – Always measured in kilograms (kg) in SI and grams (g) in CGS. ❌ Incorrect
(c) Force – Has different units in SI and CGS:
SI Unit: Newton (N)
CGS Unit: Dyne (1 N = 10⁵ Dynes)
🟢 Correct answer
(d) Electric Charge – Always measured in Coulombs (C) in SI and CGS. ❌ Incorrect
🔴 Important Points:
SI unit of Force = Newton (N).
CGS unit of Force = Dyne (1 N = 10⁵ Dyne).
Force is a vector quantity (it has both magnitude and direction).
Newton’s second law: F = ma.
Dyne is a much smaller unit than Newton.
MCQ 2 (NEET 2020)
Which of the following pairs have identical dimensions?
🔘 a) Work and Power
🔘 b) Energy and Torque
🔘 c) Force and Work
🔘 d) Impulse and Power
✅ Answer: 🟢 (b) Energy and Torque
Explanation:
(a) Work (ML²T⁻²) and Power (ML²T⁻³) – ❌ Different dimensions.
(b) Energy (ML²T⁻²) and Torque (ML²T⁻²) – 🟢 Identical dimensions.
(c) Force (MLT⁻²) and Work (ML²T⁻²) – ❌ Different dimensions.
(d) Impulse (MLT⁻¹) and Power (ML²T⁻³) – ❌ Different dimensions.
🟡 Important Points:
Torque (τ) = Force × Distance (ML²T⁻²).
Work (W) = Force × Displacement (ML²T⁻²).
🔴 SI unit of Energy & Torque = Joule (J) & Newton-meter (Nm).
Dimensional analysis helps in checking correctness of formulas.
Power (Work/Time) has different dimensions than Work.
MCQ 3 (JEE Advanced 2018)
A dimensionally correct equation is:
🔘 a) v = u + at
🔘 b) s = ut + ½ at²
🔘 c) E = mc²
🔘 d) All of the above
✅ Answer: 🟢 (d) All of the above
Explanation:
(a) v = u + at: Velocity (LT⁻¹) = (LT⁻¹) + (LT⁻² × T) → ✅ Correct.
(b) s = ut + ½ at²: Displacement (L) = (LT⁻¹ × T) + (LT⁻² × T²) → ✅ Correct.
(c) E = mc²: Energy (ML²T⁻²) = Mass (M) × (LT⁻¹)² → ✅ Correct.
(d) All of the above: 🟢 All three equations are dimensionally correct.
🟠 Important Points:
Dimensional consistency ensures equation correctness.
🔴 Power of units must match on both sides.
E = mc² explains energy-mass equivalence in relativity.
s = ut + ½ at² used in kinematics.
🔵 If an equation is dimensionally incorrect, it must be wrong.
MCQ 4 (CET 2019)
Which of the following has the same unit as angular velocity?
🔘 a) Frequency
🔘 b) Acceleration
🔘 c) Energy
🔘 d) Force
✅ Answer: 🟢 (a) Frequency
Explanation:
(a) Frequency: 🟢 Both have SI unit s⁻¹ (Hz for frequency, rad/s for angular velocity).
(b) Acceleration: m/s² (Different unit).
(c) Energy: Joule (Different unit).
(d) Force: Newton (Different unit).
🟡 Important Points:
Angular velocity (ω) = Change in angle / Time.
🔴 SI unit of angular velocity = rad/s.
Frequency (ν) = 1 / Time.
🟠 Frequency and angular velocity both measured in s⁻¹.
Rotational motion concepts use angular velocity & frequency.
I have continued adding more MCQs as per your format. Let me know if you need further modifications or additional MCQs. 🚀
Class 11 Physics - Chapter 1: Physical World & Measurement
MCQ 1 (JEE Main 2021)
A physical quantity that has different units in different measurement systems is:
🔘 a) Time
🔘 b) Mass
🔘 c) Force
🔘 d) Electric charge
✅ Answer: 🟢 (c) Force
Explanation:
(a) Time – Always measured in seconds in SI and CGS systems. ❌ Incorrect
(b) Mass – Always measured in kilograms (kg) in SI and grams (g) in CGS. ❌ Incorrect
(c) Force – Has different units in SI and CGS:
SI Unit: Newton (N)
CGS Unit: Dyne (1 N = 10⁵ Dynes)
🟢 Correct answer
(d) Electric Charge – Always measured in Coulombs (C) in SI and CGS. ❌ Incorrect
🔴 Important Points:
SI unit of Force = Newton (N).
CGS unit of Force = Dyne (1 N = 10⁵ Dyne).
Force is a vector quantity (it has both magnitude and direction).
Newton’s second law: F = ma.
Dyne is a much smaller unit than Newton.
MCQ 2 (NEET 2020)
Which of the following pairs have identical dimensions?
🔘 a) Work and Power
🔘 b) Energy and Torque
🔘 c) Force and Work
🔘 d) Impulse and Power
✅ Answer: 🟢 (b) Energy and Torque
Explanation:
(a) Work (ML²T⁻²) and Power (ML²T⁻³) – ❌ Different dimensions.
(b) Energy (ML²T⁻²) and Torque (ML²T⁻²) – 🟢 Identical dimensions.
(c) Force (MLT⁻²) and Work (ML²T⁻²) – ❌ Different dimensions.
(d) Impulse (MLT⁻¹) and Power (ML²T⁻³) – ❌ Different dimensions.
🟡 Important Points:
Torque (τ) = Force × Distance (ML²T⁻²).
Work (W) = Force × Displacement (ML²T⁻²).
🔴 SI unit of Energy & Torque = Joule (J) & Newton-meter (Nm).
Dimensional analysis helps in checking correctness of formulas.
Power (Work/Time) has different dimensions than Work.
MCQ 3 (JEE Advanced 2018)
A dimensionally correct equation is:
🔘 a) v = u + at
🔘 b) s = ut + ½ at²
🔘 c) E = mc²
🔘 d) All of the above
✅ Answer: 🟢 (d) All of the above
Explanation:
(a) v = u + at: Velocity (LT⁻¹) = (LT⁻¹) + (LT⁻² × T) → ✅ Correct.
(b) s = ut + ½ at²: Displacement (L) = (LT⁻¹ × T) + (LT⁻² × T²) → ✅ Correct.
(c) E = mc²: Energy (ML²T⁻²) = Mass (M) × (LT⁻¹)² → ✅ Correct.
(d) All of the above: 🟢 All three equations are dimensionally correct.
🟠 Important Points:
Dimensional consistency ensures equation correctness.
🔴 Power of units must match on both sides.
E = mc² explains energy-mass equivalence in relativity.
s = ut + ½ at² used in kinematics.
🔵 If an equation is dimensionally incorrect, it must be wrong.
MCQ 4 (CET 2019)
Which of the following has the same unit as angular velocity?
🔘 a) Frequency
🔘 b) Acceleration
🔘 c) Energy
🔘 d) Force
✅ Answer: 🟢 (a) Frequency
Explanation:
(a) Frequency: 🟢 Both have SI unit s⁻¹ (Hz for frequency, rad/s for angular velocity).
(b) Acceleration: m/s² (Different unit).
(c) Energy: Joule (Different unit).
(d) Force: Newton (Different unit).
🟡 Important Points:
Angular velocity (ω) = Change in angle / Time.
🔴 SI unit of angular velocity = rad/s.
Frequency (ν) = 1 / Time.
🟠 Frequency and angular velocity both measured in s⁻¹.
Rotational motion concepts use angular velocity & frequency.
I have continued adding more MCQs as per your format. Let me know if you need further modifications or additional MCQs. 🚀
🔘 b) Mass
🔘 c) Force
🔘 d) Electric charge
(a) Time – Always measured in seconds in SI and CGS systems. ❌ Incorrect
(b) Mass – Always measured in kilograms (kg) in SI and grams (g) in CGS. ❌ Incorrect
(c) Force – Has different units in SI and CGS:
SI Unit: Newton (N)
CGS Unit: Dyne (1 N = 10⁵ Dynes)
🟢 Correct answer
(d) Electric Charge – Always measured in Coulombs (C) in SI and CGS. ❌ Incorrect
SI unit of Force = Newton (N).
CGS unit of Force = Dyne (1 N = 10⁵ Dyne).
Force is a vector quantity (it has both magnitude and direction).
Newton’s second law: F = ma.
Dyne is a much smaller unit than Newton.
🔘 b) Energy and Torque
🔘 c) Force and Work
🔘 d) Impulse and Power
(a) Work (ML²T⁻²) and Power (ML²T⁻³) – ❌ Different dimensions.
(b) Energy (ML²T⁻²) and Torque (ML²T⁻²) – 🟢 Identical dimensions.
(c) Force (MLT⁻²) and Work (ML²T⁻²) – ❌ Different dimensions.
(d) Impulse (MLT⁻¹) and Power (ML²T⁻³) – ❌ Different dimensions.
Torque (τ) = Force × Distance (ML²T⁻²).
Work (W) = Force × Displacement (ML²T⁻²).
🔴 SI unit of Energy & Torque = Joule (J) & Newton-meter (Nm).
Dimensional analysis helps in checking correctness of formulas.
Power (Work/Time) has different dimensions than Work.
🔘 b) s = ut + ½ at²
🔘 c) E = mc²
🔘 d) All of the above
(a) v = u + at: Velocity (LT⁻¹) = (LT⁻¹) + (LT⁻² × T) → ✅ Correct.
(b) s = ut + ½ at²: Displacement (L) = (LT⁻¹ × T) + (LT⁻² × T²) → ✅ Correct.
(c) E = mc²: Energy (ML²T⁻²) = Mass (M) × (LT⁻¹)² → ✅ Correct.
(d) All of the above: 🟢 All three equations are dimensionally correct.
Dimensional consistency ensures equation correctness.
🔴 Power of units must match on both sides.
E = mc² explains energy-mass equivalence in relativity.
s = ut + ½ at² used in kinematics.
🔵 If an equation is dimensionally incorrect, it must be wrong.
🔘 b) Acceleration
🔘 c) Energy
🔘 d) Force
(a) Frequency: 🟢 Both have SI unit s⁻¹ (Hz for frequency, rad/s for angular velocity).
(b) Acceleration: m/s² (Different unit).
(c) Energy: Joule (Different unit).
(d) Force: Newton (Different unit).
Angular velocity (ω) = Change in angle / Time.
🔴 SI unit of angular velocity = rad/s.
Frequency (ν) = 1 / Time.
🟠 Frequency and angular velocity both measured in s⁻¹.
Rotational motion concepts use angular velocity & frequency.