A steel wheel of 600 mm diameter rolls on a horizontal steel rail. It carries a load of 500 N. The coefficient of rolling resistance is 0.3 mm. The force in N, necessary to roll the wheel along the rail is

In given figure, if the pressure of gas in bulb $$A$$ is $$50$$ $$cm$$ $$Hg$$ vacuum and $${P_{atm}} = 76\,cm\,Hg,$$ then height of column $$H$$ is equal to

Navier Stoke's equation represents the conservation of

A thin metal plate is exposed to solar radiation. The air and the surroundings are at $${30^ \circ }C\,.$$ The heat transfer coefficient by free convection from the upper surface of the plate is $$17.4$$ $$\,W/{m^2}K$$. The plate has an absorptivity of $$0.9$$ at solar wavelength and an emissivity of $$0.1$$ at the long wavelength. Neglecting any heat loss from the lower surface, determine the incident solar radiation intensity in $$kW/{m^2}$$ , if the measured equilibrium temperature of the plate is $${50^ \circ }C\,.$$ Stefan Boltzmannn constant is $$5.67 \times {10^{ - 8}}\,\,W/{m^2}{K^4}$$