Mechanical Engineering

Mechanical Engineering

Basic of Mechanical Engineering

published on December 04, 20103348 responses 9 3.3★ / 5

For the purpose of comparison, the steam generating capacity of a boiler is
generally expressed in terms of

equivalent evaporation
kg/hr
steam pressure
thermal efficiency

The pump with a low initial cost and low maintenance cost is

gear pump
bucket pump
double acting piston pump
centrifugal pump

A governer in an Ic engine controls the

mean speed variation
cyclic speed variation
load fluctuations
exhaust gas temperature

In vapour absorption refrigeration machine fluids used are

freon and lithium bromide
water and ammonia
brine and sulphur dioxide
air and water

Air refrigeration cycle works on the

Brayton cycle
Bell Coleman cycle
Carnot cycle
Sterling cycle

In a flange coupling, the flange bolts are designed for

fatigue
shear forces
compression
tensile forces

Cast iron contains one of the following % of carbon

0.3 to 0.6 %
0.05 to 0.3 %
0.6 to 1.3 %
2 to 4 %

Rack and pinion arrangement is used for

linear motion of rotary motion
rotary motion to rotary motion
linear to linear motion
rotary to linear motion

Two stroke IC engines are commonly used in 2 wheelers because the

power to weight ratio is high
thermal efficiency is high
lube oil consumption is less
cnoise is less

High carbon steel has a carbon content of

1 to 3 %
0.5 to 1 %
0.8 to 2 %
2 to 4 %

When water at atmospheric pressure is heated from 40 deg to 80 deg, the heat
absorbed is

sensible heat
latent heat
super heat
specific heat

For transmitting power without slip one of the following drives is used

belt drives
rope drives
cone pulleys
chain drives

For chain drives the small sprockets should have a minimum number of teeth of

17
25
27
31

First law of the thermodynamics deals with conversation of

mass
heat
momentum
energy

A belt can transmit maximum power when the total tension of the drive is

equal to the centrifugal tension
twice the centrifugal tension
three times the centrifugal tension
four times the centrifugal tension

The number of valves in a two stroke engine is

0
1
2
4

In a petrol engine the theoretical ratio of air to fuel is approximately

3:1
5:1
15:1
30:1

The centrifugal tension in belts

increase power transmission
decrease power transmission
doubles the power transmission
does not affect the power transmission in any way

A process in which no heat is supplied or rejected and entropy is constant is known
as

adiabatic process
isentroic process
polytropic process
isothermal process

Newton is a unit of

Mass
Momentum
Force
Energy