Mechanical Engineering

The locus of instantaneous center of a moving body relative to a fixed body is known as the
  • a)
    space centrode
  • b)
    bodycentrode
  • c)
    moving centrode
  • d)
    none of these
Correct answer is option 'A'. Can you explain this answer?

Yogesh Kumaya answered  •  1 hour ago
A centrode is the locus of the I-center of a plane body relative to another plane body for the range of motion specified or during a finite period of time.
Space centrode (or fixed centrode) is the locus of the I-center of the moving body relative to the fixed body.
Body centrode (or moving centrode) is the locus of the I-center of the fixed body relative to the movable body.

Which one of the following portions of the loaded beam shown in the given figure is subjected to pure bending?
  • a)
    AB
  • b)
    DE
  • c)
    AE
  • d)
    BD
Correct answer is option 'D'. Can you explain this answer?

Harish Lal answered  •  1 hour ago
Since the given beam is loaded symmetrically, therefore the reactions at each suportwill be equal i.e. W

In section BD, shear force is zero. Hence this section subjected to pure bending.

Dynamic similarity between model and prototype implies that
  • a)
    the forces acting at corresponding locations are same
  • b)
    the flow pattern is similar
  • c)
    there is point to point correspondence between the two systems
  • d)
    both the systems undergo similar rates of change of motion
Correct answer is option 'A'. Can you explain this answer?

Karan Kumar answered  •  14 hours ago
Two systems are dynamically similar , if geometric and kinematic similarities exist and further the ratios of all corresponding forces in the two systems are the same.
If forces due to
and suffixees m and p stand for model and prototype respectively, strict dynamic similarity means:

An SI engine sometimes continues to run for a very small period even after the ignition is switched off. This phenomenon is called
  • a)
    over burning
  • b)
    pull up period
  • c)
    dieseling
  • d)
    throttle sticking
Correct answer is option 'C'. Can you explain this answer?

GAJENDER SINGH answered  •  14 hours ago
An Si engine sometimes continues to run for a very small even after the ignition is switched off. It is called as dieseiing. Dieseling may take place due to following:
  • High engine idling speed.
  • Increase in compression ratio due to carbon deposits.
  • Engine overheating.
  • Too high spark plug heat range,
  • Incorrect adjustment of idle fuel-air mixture.
  • Sticking of throttle. 
  • Requirement of tune up of engine.
  • Oil entry into the cylinder.

Navier-Stokes equation represents the conservation of
  • a)
    energy
  • b)
    momentum
  • c)
    pressure
  • d)
    mass
Correct answer is option 'B'. Can you explain this answer?

SANJEEO SHRIVASTAVA answered  •  14 hours ago
The Navier-Stokes equations govern the motion of fluids and can be seen as Newton's second law of motion for fluids. ... The Navier-Stokes equations represent the conservation of momentum, while the continuity equation represents the conservation of mass.

Fetching relevant content for you