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Important points of Engineering Mechanics

Important points of Engineering Mechanics

  • Force = Newton
  • 1 kgf = 9.8 N
  • Process of finding force = Co position
  • Vector method =  Polygon law force
  • Resultant force = sq.root (2P)
  • sigma H = Equilibrium
  • Sigma R = Not Equilibrium
  • Mass Moment of Inertia = kg-m2
  • Movement of inertia = m4


Important points of Engineering Mechanics

  • Moment of inertia rectangle to width = (1/12)bd3
  • Moment of inertia rectangle to depth = (1/12)db3
  • Moment of inertia sphere = (a4)/12
  • Moment of inertia of circle about diameter = (pi/64)d4
  • Moment of inertia of circle about axis = (pi/32)d4
  • Moment of inertia triangle about base = (bh3)/36
  • Moment of inertia triangle about axis = (bh3)/12
  • Moment of inertia solid sphere = (2mr2)/5
  • Ideal machine efficiency = 100%
  • Non reversible machine =  self locking
  • Reversible machine <50%
  • Non reversible machine >50%
  • Screw jack is non reversible machine
  • Low power machine (P) = mW +  c , P=effort , W= Load
  • Maximum advantage lifting machine = (1/m)
  • Max. efficiency of lifting machine = (1/m)  X V.R.(Velocity Ratio)
  • Velocity ratio of 1st system pulley = 2^n
  • velocity ratio of 2nd system pulley = n
  • Velocity ratio of 1st system pulley = [(2^n)-1]
  • Velocity ratio screw jack = [(2 x pi x l)/P]
  • Redundant frame = imperfect
  • Time of flight of projectile = [2usin(alpha)]/g  
  • Angle of banking = slope on rod surface provided on curve
  • Super elevation = When railway (roadway) path outer edge is always made higher than the inner edge to keep the vehicle equilibrium while in motion this raise is known as super elevation.
  • Work =(N-m = Joule) Force act on body and body tends to move in direction of force .
  • Power [(N-m)/s][watts] = rate of doing work.

Important points of Engineering Mechanics

  • Energy = Capacity of doing work.
  • Slope provide  on road = angle of bank
  • D-Alembert principle = the resultant force acting on body together with effective reversal force are in equilibrium
  • Newton's First law = Everybody is continuous in state of rest or uniform motion in straight line unless it is acted by some of force
  • Newton;s second law = rate of change of moment is directly pro personal to impressed force takes place in the same direction in the direction of force.
  • Newton's third law = every action has equal and opposite reaction'
  • Mass = mater contains in body.
  • Weight = Force by which is attracted to words the center of earth.
  • momentum = mass  X velocity
What is the importance of engineering mechanics? - Quora
Law of static friction
  1. it acts opposite direction of body
  2. Force is exactly equal to force tends to move
  3. constant ration to limiting friction
  4. depends upon the roughness of surface
  5. independent of area of contact
Law of Kinetic friction
  1. Always acts opposite direction.
  2. bear constant ration to normal reaction between two surface.

Important points of Engineering Mechanics 

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Location: Vadodara, Gujarat, India

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