ISRO Scientist or Engineer Refrigeration & Air-Conditioning 2019
For the following questions answer them individually
A jet of water issuing from a nozzle strikes a flat plate normally (plane of plate makes an angle $$90^\circ$$ with the axis of the jet). The plate moves towards the nozzle with a velocity of 10 m/s while the jet issuing from the nozzle has a velocity of 15 m/s. The absolute velocity components of the jet (in m/s) as it leaves the vane, parallel (x component) and normal component (y component) to the undisturbed jet are. (Neglect friction on the surface).
The overall heat transfer coefficient (U) for a composite wall of thicknesses $$x_1, x_2, x_3$$ and of corresponding thermal conductivities $$k_1, k_2, k_3$$, is given by equation
Three metal walls of the same cross-sectional area having thermal conductivities in the ratio 1:2:4 transfers heat at the rate of 3000 kJ/hr. For the same wall thickness, the
temperature drops will be in the ratio
A electric heater of exposed surface area 0.09 m$$^2$$ and output 600 watts is designed to operate fully submersed in water. When the water is at $$37^\circ C$$ and the surface coefficient of heat transfer is 285.3 W/m$$^2$$-deg C, surface temperature of the heater will be
The number of teeth of a spurgearis 30 and it rotates at 200 rpm. What will be its pitch line velocity if it has a module of ($$\frac{6}{\pi}$$) mm?
A force of 271 N is applied to the break drum of 2 m diameter in band brake system as shown in figure, where the wrapping angle is $$180^\circ$$. If the coefficient of friction between the drum and the band is 7/22, the braking torque applied in Nm is
