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Important topics in Mechanical Engineering asked during GATE-1994

**Mathematics**

- Limit
- Mean value theorem
- Linear differential equation
- Rank of matrices

**Design**

- Euler’s critical buckling load
- Tensile forces
- Period of oscillation
- Power transmitted by shafts
- Condition for self locking in screw jacks
- Hook’s law, kepler’s law,
- Tresca criteria

**Machine
Tools**

- EDM (Electro Discharge machining)
- ECM (Electro Chemical Machining)

**Joining**

- Coating to arc welding electrodes
- Natural flame in gas welding
- Oxygen to acetylene ratio

**Metal
working**

- Hot and cold working process
- Deep drawing of sheets
- Drop forging
- Extrusion

**Casting**

- Investments die casting
- Centrifugal casting
- Shell moulding

**Power
Plant**

**Fluid
machines**

- Impulse turbine
- Specific speed of pumps

**Fluid
Mechanics**

- Steam lines, path lines, steak lines
- Equipotential lines
- Prandlt’s mixing length
- Velocity potential
** **
- Meta centre
- Circulation
- Froude number, Reynolds number
- Ratio of maximum velocity to average
velocity for pipe flow
- Head loss in pipe due to friction
- Bernoulli’s equation and continuity
equation
- Venturimeter
- Laminar to turbulent transition
- Separation of boundary layer
- Hydrodynamic boundary layer

**Heat
and mass transfer**

- Thermal conductivity
- Shape factor, view factor

**Refrigeration**

- Coefficient of performance

**Strength
of material**

- Ratio of maximum shear stress to average
shear stress in rectangular section

**Thermodynamics**

- Definition of
Kelvin
- Gas turbine cycle
- Stirling cycle
- Atkinson cycle
- Ericson cycle
- Brayton cycle
- Isothermal
compressibility, isentropic compressibility
- Joule Thompson
coefficient
- Isobaric thermal
expansion coefficient

**Engineering
Mechanics**

- Tension in rotating mass
- Motion of projectile
- Force of friction
- Collision’s of elastic bodies