Question
Question: Sometimes it is convenient to construct a system of units so that all quantities can be expressed in...
Sometimes it is convenient to construct a system of units so that all quantities can be expressed in terms of only one physical quantity. In one such system, dimensions of different quantities are given in terms of a quantity willows [position] [X"] [speed] [X] [acceleration] [X] [linear momentum] [X] [force] [X] Then which one is correct from the following two-

γδέττα
γδ-r-β
Both α + p = 2β and p + q - r = β are correct.
Solution
The problem asks to identify correct relationships between exponents (α, β, p, q, r) representing the dimensions of physical quantities in a system where all quantities are expressed in terms of a single quantity 'X'.
Let the dimensions of Length, Mass, and Time be [L], [M], and [T] respectively. The given dimensional relations are:
- [Position] = [L] = [X^α]
- [Speed] = [L T⁻¹] = [X^β]
- [Acceleration] = [L T⁻²] = [X^p]
- [Linear momentum] = [M L T⁻¹] = [X^q]
- [Force] = [M L T⁻²] = [X^r]
We can derive relationships between the exponents using the fundamental definitions of these physical quantities.
Derivation 1: Relationship between α, β, and p
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We know that Speed is Position divided by Time: [Speed] = [Position] / [Time] [X^β] = [X^α] / [T] Therefore, [T] = [X^α] / [X^β] = [X^(α-β)] (Equation A)
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We also know that Acceleration is Position divided by Time squared: [Acceleration] = [Position] / [Time]² [X^p] = [X^α] / [T]² Therefore, [T]² = [X^α] / [X^p] = [X^(α-p)] Taking the square root, [T] = [X^((α-p)/2)] (Equation B)
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Equating the expressions for [T] from (A) and (B): [X^(α-β)] = [X^((α-p)/2)] Comparing the exponents: α - β = (α - p) / 2 2(α - β) = α - p 2α - 2β = α - p Rearranging the terms, we get: α + p = 2β
Derivation 2: Relationship between p, q, r, and β
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We know that Force is Mass times Acceleration: [Force] = [Mass] × [Acceleration] [X^r] = [Mass] × [X^p] Therefore, [Mass] = [X^r] / [X^p] = [X^(r-p)] (Equation C)
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We also know that Linear momentum is Mass times Speed: [Linear momentum] = [Mass] × [Speed] [X^q] = [Mass] × [X^β] Therefore, [Mass] = [X^q] / [X^β] = [X^(q-β)] (Equation D)
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Equating the expressions for [Mass] from (C) and (D): [X^(r-p)] = [X^(q-β)] Comparing the exponents: r - p = q - β Rearranging the terms, we get: p + q - r = β
The question provides options as "(1) γδέττα" and "(11) γδ-r-β", which are symbolic representations. Based on dimensional analysis, the two correct relationships that can be derived are:
- α + p = 2β
- p + q - r = β
Both of these relationships are dimensionally consistent and correct.
The final answer is Both \alpha+ p = 2\beta and p + q - r = \beta are correct.
Explanation of the solution: By expressing the fundamental dimensions (Length, Mass, Time) in terms of the given quantity 'X' and its exponents (α, β, p, q, r), we use the definitions of physical quantities (speed = position/time, acceleration = position/time², force = mass × acceleration, momentum = mass × speed) to establish relationships between these exponents. This leads to two correct relationships: α + p = 2β and p + q - r = β.
Answer: The correct relationships are:
- α+p=2β
- p+q−r=β