A beaker contains a fluid of density ρ kg / m3 , specific heat SJ/kgºC and viscosity η. The beaker is filled upto height h. To estimate the rate of heat transfer per unit area (Q/A) by convection when beaker is put on a hot plate, a student proposes that it should depend on η, (sΔθ/h) and (1/ρh) when Δθ (in ºC) is the difference in the temperature between the bottom and top of the fluid. In that situation the correct option for (Q/A) is :
(1) η (sΔθ/h) (1/ρh)
(2) (sΔθ/ηh) (1/ρh)
(3) sΔθ/ηh
(4) η sΔθ/h