Heat and Mass Transfer
If the energy radiated per second per sq. cm. of the surface for wave lengths lying between λ, and λ + dλ is represented by (eλ.dλ), then eλ is called

Emissivity
Emissive power
None of these
Absorptive power

ANSWER DOWNLOAD EXAMIANS APP

Heat and Mass Transfer
The time constant of a thermocouple is

Determined by the time taken to reach 100°C from 0°C
The time taken to attain 50% of the value of initial temperature difference
The time taken to attain the final temperature to be measured
The time taken to attain 63.2% of the value of initial temperature difference

ANSWER DOWNLOAD EXAMIANS APP

Heat and Mass Transfer
Film coefficient is defined as the ratio of

Temperature drop through the films of fluids to the thickness of film of fluids
Thickness of film of fluid to the thermal conductivity
Thermal conductivity to the equivalent thickness of the film of fluid
Thickness of film of fluid to the temperature drop through the films of fluids

ANSWER DOWNLOAD EXAMIANS APP