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The variables x, v, and a have the dimen...

The variables x, v, and a have the dimensions of `[L],[L]//[T], and [L]//[T]^(2)`, respectively. These variables are related by an equation that has the form `v^(n)=2ax`, where n is an integer constant (1, 2, 3, etc.) without dimensions. What must be the value of n, so that both sides of the equation have the same dimensions? Explain your reasoning.

A

1

B

3

C

2

D

4

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem, we need to ensure that both sides of the equation \( v^n = 2ax \) have the same dimensions. Let's break down the steps to find the value of \( n \). ### Step 1: Identify the dimensions of each variable - The dimension of \( x \) is given as \( [L] \). - The dimension of \( v \) (velocity) is \( [L][T]^{-1} \). - The dimension of \( a \) (acceleration) is \( [L][T]^{-2} \). ### Step 2: Write down the dimensions of the left side of the equation The left side of the equation is \( v^n \). Therefore, we need to find the dimensions of \( v^n \): \[ \text{Dimensions of } v^n = ([L][T]^{-1})^n = [L^n][T]^{-n} \] ### Step 3: Write down the dimensions of the right side of the equation The right side of the equation is \( 2ax \). Since 2 is a dimensionless constant, we can ignore it for dimensional analysis: \[ \text{Dimensions of } 2ax = a \cdot x = ([L][T]^{-2}) \cdot [L] = [L^2][T]^{-2} \] ### Step 4: Set the dimensions of both sides equal to each other Now we set the dimensions of both sides equal: \[ [L^n][T]^{-n} = [L^2][T]^{-2} \] ### Step 5: Equate the powers of \( L \) and \( T \) From the equation \( [L^n][T]^{-n} = [L^2][T]^{-2} \), we can equate the powers of \( L \) and \( T \): 1. For \( L \): \( n = 2 \) 2. For \( T \): \( -n = -2 \) (which also gives \( n = 2 \)) ### Conclusion Both conditions give us the same result, \( n = 2 \). Therefore, the value of \( n \) must be 2 for both sides of the equation to have the same dimensions. ### Final Answer The value of \( n \) is \( 2 \). ---
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