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An air bubble of 1 cm radius is rising a...

An air bubble of 1 cm radius is rising at a steady rate of `2.00ms^-1` through a liquid of density `1.5gcm^-3`. Neglect density of air. If `g=1000cms^-2`, then the coeffieciet of viscosity of the liquid is

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To find the coefficient of viscosity of the liquid through which an air bubble is rising, we can use the formula derived from Stokes' law for the motion of a sphere through a viscous medium. The formula is: \[ \eta = \frac{2r^2 \rho g}{9v} \] where: - \( \eta \) is the coefficient of viscosity, - \( r \) is the radius of the bubble, - \( \rho \) is the density of the liquid, - \( g \) is the acceleration due to gravity, - \( v \) is the velocity of the bubble. ### Step-by-Step Solution: 1. **Identify and convert the given values:** - Radius of the bubble, \( r = 1 \, \text{cm} = 0.01 \, \text{m} \) (or \( 1 \, \text{cm} \) directly in calculations). - Velocity of the bubble, \( v = 2 \, \text{m/s} = 200 \, \text{cm/s} \). - Density of the liquid, \( \rho = 1.5 \, \text{g/cm}^3 = 1.5 \times 1000 \, \text{kg/m}^3 = 1500 \, \text{kg/m}^3 \). - Acceleration due to gravity, \( g = 1000 \, \text{cm/s}^2 = 10 \, \text{m/s}^2 \). 2. **Substitute the values into the viscosity formula:** \[ \eta = \frac{2 \times (1 \, \text{cm})^2 \times (1.5 \, \text{g/cm}^3) \times (1000 \, \text{cm/s}^2)}{9 \times (200 \, \text{cm/s})} \] 3. **Calculate the numerator:** - Convert the radius to cm for consistency: \[ 2 \times (1)^2 \times 1.5 \times 1000 = 3000 \, \text{g cm/s}^2 \] 4. **Calculate the denominator:** \[ 9 \times 200 = 1800 \, \text{cm/s} \] 5. **Calculate the coefficient of viscosity:** \[ \eta = \frac{3000 \, \text{g cm/s}^2}{1800 \, \text{cm/s}} = \frac{3000}{1800} = \frac{5}{3} \, \text{g/cm/s}^2 \] 6. **Convert to poise:** - Since \( 1 \, \text{poise} = 1 \, \text{g/cm/s}^2 \): \[ \eta = \frac{5}{3} \, \text{poise} \] ### Final Answer: The coefficient of viscosity of the liquid is \( \frac{5}{3} \, \text{poise} \).

To find the coefficient of viscosity of the liquid through which an air bubble is rising, we can use the formula derived from Stokes' law for the motion of a sphere through a viscous medium. The formula is: \[ \eta = \frac{2r^2 \rho g}{9v} \] where: - \( \eta \) is the coefficient of viscosity, ...
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