## Compressors, Gas Turbines and Jet Engines The thrust on the rotor in a centrifugal compressor is produced by

None of these
Axial component
Tangential component

Any one of these
Isentropic
Isothermal
Polytropic

## Compressors, Gas Turbines and Jet Engines In a single stage, single acting reciprocating air compressor without clearance volume, the work-done is maximum during

Isentropic compression
Isothermal compression
Polytropic compression
None of these

## Compressors, Gas Turbines and Jet Engines Gas turbine blades are given a rake

Opposite to the direction of motion of blades
Equal to zero
In the direction of motion of blades
Depending on the velocity

## Compressors, Gas Turbines and Jet Engines If p₁ is the pressure of air entering the L.P, cylinder and p₃ is the pressure of air leaving the H.P. cylinder, then the ratio of cylinder diameters for a single acting, two stage reciprocating compressor with complete intercooling is given by

D₁/D₂ = (p₁/p₃)1/4
D₁/D₂ = (p₃/p₁)1/4
D₁/D₂ = (p₁ p₃)1/4
D₁/D₂ = (p₁ p₃)1/2

## Compressors, Gas Turbines and Jet Engines Losses in a centrifugal compressor are due to

Impeller channel losses
All of the listed here
Diffuser losses
Inlet losses