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In dimension of critical velocity v(c) l...

In dimension of critical velocity `v_(c)` liquid following through a take are expressed as `(eta^(x) rho^(y) r^(z))` where `eta, rhoand r `are the coefficient of viscosity of liquid, density of liquid and radius of the tube respectively then the value of `x,y` and `z` are given by

A

`1,-1,-1`

B

`-1,-1,1`

C

`-1,-1,-1`

D

`1,1,1`

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To determine the values of \( x \), \( y \), and \( z \) in the expression for the critical velocity \( v_c \) in terms of the coefficient of viscosity \( \eta \), density \( \rho \), and radius \( r \), we need to equate the dimensions on both sides of the equation: \[ v_c = \eta^x \rho^y r^z \] ### Step-by-Step Solution: 1. **Write the dimensional formula for each quantity:** - Critical velocity \( v_c \): \([v_c] = [L^1 T^{-1}]\) - Coefficient of viscosity \( \eta \): \([ \eta ] = [M^1 L^{-1} T^{-1}]\) - Density \( \rho \): \([ \rho ] = [M^1 L^{-3} T^0]\) - Radius \( r \): \([ r ] = [L^1]\) 2. **Express the dimensional equation:** \[ [v_c] = [\eta^x \rho^y r^z] \] Substituting the dimensions: \[ [L^1 T^{-1}] = [M^1 L^{-1} T^{-1}]^x [M^1 L^{-3} T^0]^y [L^1]^z \] 3. **Expand the dimensions:** \[ [L^1 T^{-1}] = [M^x L^{-x} T^{-x}] [M^y L^{-3y} T^0] [L^z] \] 4. **Combine the dimensions:** \[ [L^1 T^{-1}] = [M^{x+y} L^{-x-3y+z} T^{-x}] \] 5. **Equate the dimensions on both sides:** - For mass \( M \): \[ x + y = 0 \quad \text{(1)} \] - For length \( L \): \[ -x - 3y + z = 1 \quad \text{(2)} \] - For time \( T \): \[ -x = -1 \quad \text{(3)} \] 6. **Solve the equations:** From equation (3): \[ x = 1 \] Substitute \( x = 1 \) into equation (1): \[ 1 + y = 0 \implies y = -1 \] Substitute \( x = 1 \) and \( y = -1 \) into equation (2): \[ -1 - 3(-1) + z = 1 \] Simplify: \[ -1 + 3 + z = 1 \implies 2 + z = 1 \implies z = -1 \] ### Final Values: \[ x = 1, \quad y = -1, \quad z = -1 \]

To determine the values of \( x \), \( y \), and \( z \) in the expression for the critical velocity \( v_c \) in terms of the coefficient of viscosity \( \eta \), density \( \rho \), and radius \( r \), we need to equate the dimensions on both sides of the equation: \[ v_c = \eta^x \rho^y r^z \] ### Step-by-Step Solution: 1. **Write the dimensional formula for each quantity:** ...
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