Find out the components of the force, Mechanical Engineering

Find out the components of the force:

The frame of a certain machine accelerates to the right at 0.8 g m/sec2. As illustrated in Figure, it carries a uniform bent bar ABC weighing 50 N/m, pinned to it at C and braced by the consistent strut DE which weighs 100 N. Find out the components of the force at pin D.


Except for the application of inertia forces the solution of this problem is same as that for statics. The free body diagram of each of member is placed in dynamic equilibrium including inertia force acting through the C. G. of each of part, directed opposite to the acceleration. We should note that instead of locating C. G. for ABC, it is more suitable to apply the inertia reaction acting on each of part of its length. The inertia forces are

For AB,

                                   ma/g = 15 . a = (15/g) × 0.8 g = 12 N

For BC,

                                    ma = (25/g) . a = (25/g) × 0.8 g = 20 N

For DE,

                               ma = (100/g) . a = (100/g) × 0.8 g = 80 N

Now Let us consider FBD of ABC.

Sum of moments about C shall eliminate three unknown forces and we get, directly Dx.

                                      ∴ ∑ M C  = 0

                - M AB × 15 - FAB × 50 - FBC  × 25 + Dx  × 35 = 0

(MBC has not been taken because this is acting vertically which passes through point C).

∴ - 15 × 15 - 12 ×50 - 20 × 25 + Dx  × 35 = 0

∴ Dx  = 37.8 N

Referring to FBD of DE now in which Dx is known, we take sum of moments about E which shall remove Ex and Ey.

∴ ∑ M E  = 0

∴ - 37.8 × 35 - 80 × 17.5 - 100 × 12.5 + Dy × 25 = 0

∴ Dy  = 158.92 N

If needed, components of reactions at C and E may be determined by applying

∑ Fx  = 0, ∑ Fy  = 0 , to each body separately.

The body of mass 100 kg is supported by wheels at B which freely roll without friction and by a skid at A under which the coefficient of friction is equal to 0.5. Calculate the value of P to cause an acceleration of (g/4) m / sec2 .

Posted Date: 1/29/2013 2:46:03 AM | Location : United States

Related Discussions:- Find out the components of the force, Assignment Help, Ask Question on Find out the components of the force, Get Answer, Expert's Help, Find out the components of the force Discussions

Write discussion on Find out the components of the force
Your posts are moderated
Related Questions

An open-loop control system has the following state-space model: (a)  Determine the characteristic equation for the open-loop control system. (b)  Determine the characte

(a) Explain various types of methods of refrigeration. (b) Write the factors consideration for the selection of refrigerant for a system. A 5 tonne refrigerating machine oper

Nominal Stress and True Stress: Nominal stress is the ratio of force per initial cross sectional area (original area of cross section). Nominal stress = Force / initial ar

how we can design a shaft for gear box

Gibson Ltd operates sportswear stores in Dublin and Cork and has set the following quarterly sales target for international and provlncial rugby shirts for 2013 per the attached sc

Ladder friction: .: A ladder is an arrangement which is used for climbing on the walls. It consists of two long uprights of wood or iron and connected by many cross bars. Th

Advantage of flash butt welding 1. Higher weld strength 2. Higher production rate 3. Better heat concentration 4. Simple weld surface preparation 5. Wide range of m

PRINCIPLE OF SUBMERGED ARC WELDING In submerged arc welding, the arc zone is submerged beneath the molten flux and hence there is no visible signature of the arc. Welding current

Inventor claims in adiabatic system: On e inventor claims that 2 kg of air supplied to magic tube at 4 bar and 20°C and the two equal mass streams at 1 bar are produced, one