ISRO Scientist or Engineer Refrigeration & Air-Conditioning 2015

When a body slides down a surface inclined $$\theta$$ to horizontal, the acceleration (f) of the body is given by

If $$\sigma_1$$ and $$\sigma_2$$ be the major and minor tensile stresses, then maximum value of tangential stress is equal to

The pressure in the air space above an oil (sp. Gravity 0.7) surface in a tank is 0.1 kg/cm$$^2$$. The pressure at 5 m below theoil surface will be

Thermal weldingis a form of

The ratio of heat flow $$\frac{Q_1}{Q_2}$$ from two walls of same thickness having their thermal conductivities as $$K_1 = 2K_2$$ will be

A Carnot engine has an efficiency of 0.5. The COP ofrefrigerant working with the same temperature limit is

Slack represent the difference between the

A refrigerator operates on a reverse Carnot eycle between 900 and 300 k. If heat at the rate of 3 kJ/s is extracted from the low temperature space, then the power required to drive the refrigerator

If V is the mean velocity of flow, then according to Darcy-Weisbach equation for pipe flow energy loss over a length of pipeline is proportional to

40% of incident radiant energy on the surface of a thermally transparent bodyis reflected back. Ifthe transmissivitiy of the body be 0.15, then the emissivity of surface is