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The Grashoff number is defined as the ratio of the

Q.  
The Grashoff number is defined as the ratio of the


Answer & Explanation

The Grashoff number is defined as the ratio of the buoyancy to viscous forces.

Thus correct option is: B.

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More Questions Heat and Mass Transfer:

Q.  
Fluid motion in the natural convection heat transfer between a solid surface and a fluid in contact with it, results from the

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B. temperature gradient produced due to density difference

C. buoyancy of the bubbles produced at active nucleation site

D. none of these


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Thermal conductivity of a gas at low density, ______ with increase in temperature.

A. Decreases

B. Increases

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Slab made up of carbon steel is initially at a temperature of 500°C (Ti) and it is exposed to air at 30°C (Ta). The thickness of the slab is 1 cm (L). What will be the temperature of the slab after one minute (t)? Assume that the convective heat transfer coefficient (h) on the surface of the slab is 40 W/m2K.

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