Reactions at point while the system is rotating, Mechanical Engineering

Reactions at point while the system is rotating:

8 kg ball is mounted on a horizontal bar associated to a vertical shaft. Neglecting the mass of the bar and shaft what are the reactions at B and C while the system is rotating at a constant speed of 90 rpm.


Free body diagram of the system is illustrated in Figure (b) above. Reactions at B, i.e. Bx and By are marked as shown. Likewise, reaction at C is also marked. As the vertical shaft rotates, the ball shall traverse a horizontal circular path of radius 300 mm, inertia force of mrω2 shall be acting on the ball as illustrated in the diagram.

Now, we write down dynamic equilibrium equations for the same.

∑ Fx  = 0,          ∴ Cx  + Bx  - 8 × 0.3 × ω2 = 0

ω = 2 π n/60 =( 2 π × 90)/60 = 9.42 rad / sec

C x  + Bx  = 8 × 0.3 × (9.42)2

∴ C x  + Bx  = 212.97                                  --------- (1)

∑ Fy  = 0,       By  - 8 × 9.81 = 0                       -------- (2)

∴ By  = 78.48 N

∑ M A  = 0,          ∴ Cx × 0.9 - Bx × 0.3 - By × 0.3 = 0

 or,       0.9 Cx - 0.3 Bx = 23.54

∴ Bx  = 140 N

  C x  = 72.9 N

  By  = 78.48 N

Posted Date: 1/29/2013 6:38:34 AM | Location : United States

Related Discussions:- Reactions at point while the system is rotating, Assignment Help, Ask Question on Reactions at point while the system is rotating, Get Answer, Expert's Help, Reactions at point while the system is rotating Discussions

Write discussion on Reactions at point while the system is rotating
Your posts are moderated
Related Questions
A load cell based on a "proving ring" is shown below.  The circular portion of the load cell has an inner radius of 1.25 in and outer radius of 1.50 in.  The ring has a depth (i.e.

An experiment to determine the convection coefficient associated with airflow over the surface of a thick stainless steel casting involves insertion of thermocouples in the casting

What do you mean by thermodynamic equilibrium? Compare irreversible process with reversible process. Give some examples of irreversible process.

Cell-decomposition In cell-decomposition, an object can be represented as the sum of cells into which it can be decomposed. Each cell-decomposition system defines a set of prim

Isolated and Combined Footings Individual columns are generally supported on isolated footings. A typical isolated footing is shown in Figure. This arrangement is suitable when

How to determine Forces and Torque of slider crank mechanism?

Scope of strength of materials: What is the scope of strength of materials? Sol.: Strength of materials is science that deals with the relations between externally appl

Consider the robotic manipulator of Fig. 1, with a Revolute and a Prismatic Joint. Figure 1, shows the side view of the manipulator while figure 2. shows the top view of the manipu