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Match the LIST-I with LIST-II
LIST-ILIST-II
A. Gravitational constantI. [LT^-2]
B. Gravitational potential energyII. [L^2T^-2]
C. Gravitational potentialIII. [ML^2T^-2]
D. Acceleration due to gravityIV. [M^-1L^3T^-2]
Choose the correct answer from the options given below:

Solution & Explanation

### Related Formula Newton's Law of Gravitation: F = Gfracm_1 m_2r^2 implies G = fracFr^2m_1 m_2 Potential Energy: U = mgh quad [textWork] Potential: V = fracWm Acceleration: g = fractextVelocitytextTime ### Core Logic Let's perform dimensional analysis for each item: 1. **A. Gravitational constant (G)**: [G] = frac[F][r^2][M^2] = frac[MLT^-2][L^2][M^2] = [M^-1L^3T^-2] Matches with **IV**. 2. **B. Gravitational potential energy (U)**: [U] = textDimensions of Work = [ML^2T^-2] Matches with **III**. 3. **C. Gravitational potential (V)**: [V] = frac[textEnergy][M] = frac[ML^2T^-2][M] = [L^2T^-2] Matches with **II**. 4. **D. Acceleration due to gravity (g)**: [g] = [textAcceleration] = [LT^-2] Matches with **I**. ### Step 1: Match and Selection Let's align our matches: - A rightarrow IV - B rightarrow III - C rightarrow II - D rightarrow I This sequence matches option (1). ### Pattern Recognition To save precious exam time on match-the-column questions, start with the easiest dimensional terms first. You know Acceleration due to gravity is g rightarrow [LT^-2] (D-I) and energy is [ML^2T^-2] (B-III). Looking at the options, only Option 1 matches this sequence immediately! ### Evaluation Rubric / Model Answer null ### Chapter Mix Class 11 Physics: Units and Measurements Class 11 Physics: Gravitation

Reference Study Guides

More Units and Measurements Previous-Year Questions

Q7 2025 Dimensional Analysis
Given a charge q, current I and permeability of vacuum mu_0 . Which of the following quantity has the dimension of momentum?
  • A. q I / mu_0
  • B. q mu_0 I
  • C. q^2 mu_0 I
  • D. q mu_0 / I

Solution

### Related Formula Let momentum be P ([P] = [M L T^-1]). We assume: P = q^x mu_0^y I^z ### Core Logic Let's find the dimensional formulas of the individual variables: 1. **Charge (q):** [q] = [A T] 2. **Current (I):** [I] = [A] 3. **Permeability of vacuum (mu_0):** From Biot-Savart law or force between parallel wires: F = fracmu_0 I^2 L2pi d: [mu_0] = frac[F][I]^2 = frac[M L T^-2][A]^2 = [M L T^-2 A^-2] ### Step 1: Apply Dimensional Homogeneity Substitute these into our assumed dimensional equation: [M L T^-1] = [A T]^x [M L T^-2 A^-2]^y [A]^z [M L T^-1] = [M]^y [L]^y [T]^x - 2y [A]^x - 2y + z Comparing exponents on both sides: - For [M]: y = 1 - For [L]: y = 1 quad text(consistent) - For [T]: x - 2y = -1 implies x - 2(1) = -1 implies x = 1 - For [A]: x - 2y + z = 0 implies 1 - 2(1) + z = 0 implies z = 1 Thus, x = 1, y = 1, z = 1. Therefore, the required quantity is: q^1 mu_0^1 I^1 = q mu_0 I ### Pattern Recognition Sees: Permeability, charge, and current linked to momentum. Trap: Deriving the dimensions of mu_0 using complex magnetic formulas. Remember [mu_0] = [textForce]/[textCurrent]^2 is the quickest way to get its dimensions. Shortcut: Since [q] = AT and [I] = A, [q mu_0 I] = [A T] [M L T^-2 A^-2] [A] = [M L T^-1], which is exactly the dimensions of momentum. Hence, option (2) is correct. ### Evaluation Rubric / Model Answer null ### Chapter Mix Class 11 Physics: Units and Measurements Class 12 Physics: Moving Charges and Magnetism
Q 2025 Dimensional Analysis
Match List-I with List-II. beginarray|l|l| hline textbfList-I & textbfList-II \\ hline text(A) Coefficient of viscosity & text(I) [mathrmML^0mathrmT^-3] \\ hline text(B) Intensity of wave & text(II) [mathrmML^-2mathrmT^-2] \\ hline text(C) Pressure gradient & text(III) [mathrmM^-1mathrmLT^2] \\ hline text(D) Compressibility & text(IV) [mathrmML^-1mathrmT^-1] \\ hline endarray Choose the correct answer from the options given below:
  • A. (A)-(I), (B)-(IV), (C)-(III), (D)-(II)
  • B. (A)-(IV), (B)-(I), (C)-(II), (D)-(III)
  • C. (A)-(IV), (B)-(II), (C)-(I), (D)-(III)
  • D. (A)-(II), (B)-(III), (C)-(IV), (D)-(I)

Solution

### Related Formula Definitions of physical quantities: 1. Viscosity: F = -eta A fracdvdx 2. Intensity: I = fractextPowertextArea 3. Pressure gradient: fracdPdx 4. Compressibility: K = frac1B = fractextStraintextStress ### Core Logic Let's calculate each dimensional formula: 1. **Coefficient of viscosity (eta):** [eta] = frac[F][A]left[fracdvdxright] = fractextM L T^-2textL^2 left(fractextL T^-1textLright) = textM L^-1textT^-1 Matches **(IV)**. 2. **Intensity of wave (I):** [I] = frac[textPower][textArea] = fractextM L^2textT^-3textL^2 = textM T^-3 = textM L^0textT^-3 Matches **(I)**. 3. **Pressure gradient (fracdPdx):** left[fracdPdxright] = frac[textPressure][textLength] = fractextM L^-1textT^-2textL = textM L^-2textT^-2 Matches **(II)**. 4. **Compressibility (K):** Compressibility is the inverse of Bulk Modulus: [K] = frac1[textPressure] = frac1textM L^-1textT^-2 = textM^-1textLtextT^2 Matches **(III)**. Thus: (A)-(IV), (B)-(I), (C)-(II), (D)-(III). ### Step 1: Final Conclusion The correct option is (2). ### Pattern Recognition Target basic matching terms first: Compressibility is the reciprocal of pressure, giving [M^-1LT^2]. Wave intensity has units of power per unit area, giving [MT^-3]. This immediately isolates option (2). ### Evaluation Rubric / Model Answer null ### Chapter Mix Class 11 Physics: Units and Measurements Class 11 Physics: Mechanical Properties of Fluids Class 11 Physics: Mechanical Properties of Solids
Q2 2025 Dimensional Analysis
The equation for real gas is given by left(P + fracaV^2right)(V - b) = RT, where P, V, T and R are the pressure, volume, temperature and gas constant, respectively. The dimension of ab^-2 is equivalent to that of:
  • A. Planck's constant
  • B. Compressibility
  • C. Strain
  • D. Energy density

Solution

### Related Formula By the principle of dimensional homogeneity, terms added or subtracted must have the same dimensions: [P] = left[fracaV^2right] implies [a] = [P][V]^2 [V] = [b] ### Core Logic Let's find the dimensional formula of the quantities: - Pressure P: [P] = textM L^-1textT^-2 - Volume V: [V] = textL^3 Substituting these to find [a] and [b]: [a] = (textM L^-1textT^-2)(textL^6) = textM L^5textT^-2 [b] = textL^3 implies [b^-2] = textL^-6 Now, compute the dimensions of ab^-2: [ab^-2] = (textM L^5textT^-2)(textL^-6) = textM L^-1textT^-2 This matches the dimensions of pressure. Let's evaluate the options: 1. Planck's constant: [h] = textM L^2textT^-1 2. Compressibility: [beta] = textM^-1textLtextT^2 3. Strain: dimensionless 4. Energy density (energy per unit volume): left[fracEVright] = fractextM L^2textT^-2textL^3 = textM L^-1textT^-2 ### Step 1: Final Conclusion Therefore, the dimension of ab^-2 is equivalent to that of Energy density. ### Pattern Recognition By writing the relation directly as [ab^-2] = frac[a][b]^2, and noting [a] = [P][V]^2 and [b] = [V], we get [ab^-2] = frac[P][V]^2[V]^2 = [P] (Pressure). Since pressure and energy density have identical dimensions, the answer is immediately Energy density. ### Evaluation Rubric / Model Answer null ### Chapter Mix Class 11 Physics: Units and Measurements Class 11 Physics: Kinetic Theory of Gases
Q 2025 Dimensional Analysis and Constants
Match the LIST-I with LIST-II
LIST-ILIST-II
A. Boltzmann constantI. ML^2T^-1
B. Coefficient of viscosityII. MLT^-3K^-1
C. Planck's constantIII. ML^2T^-2K^-1
D. Thermal conductivityIV. ML^-1T^-1
Choose the correct answer from the options given below :
  • A. A-III, B-IV, C-I, D-II
  • B. A-II, B-III, C-IV, D-I
  • C. A-III, B-II, C-I, D-IV
  • D. A-III, B-IV, C-II, D-I

Solution

### Related Formula Formulas to find dimensional formulas: - Boltzmann constant: k_B = fractextEnergytextTemperature - Coefficient of viscosity: eta = fracFA fracdvdx - Planck's constant: h = fracEnu - Thermal conductivity: fracdQdt = K A fracdTdx Rightarrow K = fractextHeat flow cdot textthicknesstextArea cdot textTemperature difference ### Core Logic Evaluate each constant individually: ### Step 1: Dimensions of Boltzmann constant (k_B) [k_B] = frac[ML^2T^-2][K] = [ML^2T^-2K^-1] quad Rightarrow textMatches III ### Step 2: Dimensions of Coefficient of viscosity (eta) [eta] = frac[MLT^-2][L^2] [T^-1] = [ML^-1T^-1] quad Rightarrow textMatches IV ### Step 3: Dimensions of Planck's constant (h) [h] = frac[ML^2T^-2][T^-1] = [ML^2T^-1] quad Rightarrow textMatches I ### Step 4: Dimensions of Thermal conductivity (K) [K] = frac[ML^2T^-3] [L][L^2] [K] = [MLT^-3K^-1] quad Rightarrow textMatches II This sequence yields A-III, B-IV, C-I, D-II, matching Option (1). ### Pattern Recognition To solve matching sets efficiently, search for the most recognizable dimensions first. Planck's constant h (ML^2T^-1) and viscosity coefficient eta (ML^-1T^-1) are highly unique and usually resolve the options instantly. ### Evaluation Rubric / Model Answer null ### Chapter Mix Class 11 Physics: Units and Measurements
Q25 2025 Error Analysis
A physical quantity C is related to four other quantities p, q, r and s as follows C = fracpq^2r^3sqrts The percentage errors in the measurement of p, q, r and s are 1\% , 2\% , 3\% and 2\% respectively. The percentage error in the measurement of C will be ________ \%.
Numerical Answer. Answer: 15 to 15

Solution

### Related Formula For a physical quantity defined by algebraic powers C = fracp^a q^br^c s^d, the maximum fractional error is calculated by summing absolute scaled fractional errors: fracDelta CC = a fracDelta pp + b fracDelta qq + c fracDelta rr + d fracDelta ss Expressed as percentages: \% text error in C = a(\% text error in p) + b(\% text error in q) + c(\% text error in r) + d(\% text error in s) ### Core Logic Given expression: C = p^1 q^2 r^-3 s^-1/2 Max fractional error equation: fracDelta CC = 1 left(fracDelta ppright) + 2 left(fracDelta qqright) + 3 left(fracDelta rrright) + frac12 left(fracDelta ssright) ### Step 1: Calculate the total percentage error Substitute the individual percentage errors: - Error in p = 1\% - Error in q = 2\% - Error in r = 3\% - Error in s = 2\% \% text error in C = 1(1\%) + 2(2\%) + 3(3\%) + frac12(2\%) \% text error in C = 1\% + 4\% + 9\% + 1\% = 15\% The total percentage error in C is 15\%. ### Pattern Recognition In error propagation, individual errors always combine constructively to produce the maximum possible uncertainty limit. Hence, negative powers (like division by r^3 or s^1/2) are integrated using positive coefficients during maximum absolute error summation. ### Evaluation Rubric / Model Answer null ### Chapter Mix Class 11 Physics: Units and Measurements

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