Inertia Forces in Reciprocating Parts topics include: Kliens, bennetts and ritterhaus construction, velocity and acceleration of engines, reciprocating parts of engines. Inertia forces in reciprocating parts are caused by the oscillation of reciprocating masses. These forces act along the line of stroke and through the cross head on the structures and on the main bearing of the crankshaft.  The inertia force due to the acceleration of the reciprocating parts opposes the force on the piston. The inertia force due to retardation of the reciprocating parts helps the force on the piston.  The... Show more

Inertia Forces in Reciprocating Parts topics include: Kliens, bennetts and ritterhaus construction, velocity and acceleration of engines, reciprocating parts of engines.

Inertia forces in reciprocating parts are caused by the oscillation of reciprocating masses. These forces act along the line of stroke and through the cross head on the structures and on the main bearing of the crankshaft. 

The inertia force due to the acceleration of the reciprocating parts opposes the force on the piston. The inertia force due to retardation of the reciprocating parts helps the force on the piston. 
The inertial force of mass can be calculated by multiplying the object's mass by its acceleration. 
Balancing is a method of correcting or eliminating unwanted inertia forces and couples in rotating and reciprocating parts of the machine.

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Machine Dynamics Practice Test: Inertia Forces in Reciprocating Parts

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25 Questions

1. In a horizontal engine, reciprocating parts are retarded when the piston moves from _________

TDC to BDCBDC to midwayBDC to TDCMidway to TDC

2. In a horizontal engine, reciprocating parts are accelerated when the piston moves from _______

TDC to BDCBDC to midwayBDC to TDCMidway to TDC

3. With respect to the figure given quadrilateral CQNO is known as _______

Klein’s acceleration diagramBennet’s diagramKlein’s velocity diagramKlein’s displacement diagram

4. Why the inertia torque acts in the opposite direction to the accelerating couple?

Acts as a constraint torqueTo reduce the accelerating torqueIncrease the linear accelerationBring the body in equilibrium

5. The crank and connecting rod of a steam engine are 0.3 m and 1.5 m in length. The crank rotates at 150 r.p.m. clockwise, determine velocity of the piston when the crank is at an angle 40 degrees from IDC.

3.493.364.195

6. Piston effort acts along the line of stroke.

MaybeFalseDon't KnowTrue

7. From figure, acceleration of P with respect to C is given by_________

ω2.CNω2.OMω2.PCω2.QN

8. Ritterhaus’ construction is used when the motion of the crank is linear shm.

MaybeTrueFalseDon't Know

9. From figure, what is the absolute velocity of P, i.e velocity of P with respect to the stationary point O?

ω × CMω × OMω × QNω × OC

10. The net force acting on the crosshead pin is known as __________

Crank pin effortShaft effortCrank effortPiston effort

11. Klein’s construction gives a graphical construction of a 4 bar chain.

TrueMaybeDon't KnowFalse

12. If the crank and the connecting rod are 300 mm and 1 m long respectively and the crank rotates at a constant speed of 250 r.p.m., determine the crank angle at which the maximum velocity occurs is ____

45756090

13. Crank effort is the product of crank pin radius and _______

Force acting along connecting rodThrust on sidesPiston effortCrankpin effort

14. From figure, what is the velocity of P with respect to C?

ω × CMω × OCω × QNω × OM

15. In a slider crank mechanism, the length of the crank and connecting rod are 150 mm and 600 mm respectively. The crank position is 60° from inner dead centre. The crank shaft speed is 400 r.p.m. (clockwise). Velocity of the slider is ________

7.32 m/s6.9 m/s6.12 m/s6.66 m/s

16. In which of the following cases Ritterhaus’ construction can be used?

Crank has a uniform angular velocityLever has a uniform angular accelerationWhen the motion is SHMCrank has a uniform angular acceleration

17. If the crank and the connecting rod are 600 mm and 2 m long respectively and the crank rotates at a constant speed of 250 r.p.m, determine maximum velocity of the piston in m/s is _____

1510.52017.5

18. When the acceleration of the piston is 0, then the velocity is _____

MinimumHalf the maximumNegativeMaximum

19. From the data given:
The length of the crank and connecting rod are 150 mm and 600 mm
The crank position is 60° from inner dead centre. The crank shaft speed is 400 r.p.m.
Find the angular acceleration in rad/s² of the connecting rod.

400421388379

20. In the expression F – m.a = 0, the term – m.a is called _______

Coriolis forceReversed effective forceNet forceResultant force

21. In the presence of frictional resistance, the expression for piston effort is _________

F(L) – F(I)F(L) – F(I) + R(f)F(L) ± F(I) – R(f)F(L) + F(I)

22. From the data given:
Crank and connecting rod of a steam engine are 0.3 m and 1.5 m in length; The crank rotates at 150 r.p.m. clockwise.
Determine the acceleration in m/s² of the piston for the same position(angle 40 degrees from IDC).

50.4155.2559.2765.3

23. From figure, acceleration of P with respect to C is given by_________

ω2.CNω2.QNω2.OMω2.PC

24. In a horizontal engine, the weight of the reciprocating parts also add/subtract to the piston effort.

Don't KnowMaybeFalseTrue

25. For a slider crank mechanism, the total no. of dead centres are _____

2130