A formula for calculating Grashof number: (gcdot beta cdot Delta tcdot l^2)/(v^3) (gcdot beta cdot Delta tcdot l^3)/(vcdot a) (gcdot beta cdot Delta tcdot l^3)/(v^2) (gcdot beta cdot t_(c)cdot l^3)/(v^2)

Grashof number is a dimensionless quantity used in fluid mechanics to characterize the flow regime in natural convection. It is defined as the ratio of the buoyancy force to the viscous force. The correct formula for calculating Grashof number is: where:- is the acceleration due to gravity,- is the coefficient of thermal expansion,- is the temperature difference,- is the characteristic length (e.g., the height of the heated surface),- is the kinematic viscosity of the fluid.The other formulas provided are incorrect and do not represent the correct formula for calculating Grashof number.