Compute the coefficient of friction at block, Mechanical Engineering

Compute the coefficient of friction at block:

The frame shown in Figure rotates about a vertical axis. The coefficient of friction under block A is 0.4. Compute the coefficient of friction at block B if B starts to rise when the frame rotates at 40 rpm.

1885_Compute the coefficient of friction at block.jpg

Solution

As the table rotates, block A shall try to move outwards.

We have,        ω = (40 × 2 π )/60

                       = 4.19 rad / sec

The acceleration acting on Block A towards axis of rotation shall be

r ω2 = 21.06 m / sec2            (r = 1.2 m)

let FBD of Block A (Figure (b)), writing equilibrium equation, we have

T =   (100/g )  × an  - F

We get,

T = (100 /g) × an - 0.4 F1

= (100 /9.81) × 21.06 - 0.4 × 100

= 174.67 N

Now considering FBD of Block B, (Figure (c)).

Figure 6.15(c)

We get,

T = 80 + (80 /9.81) × 21.06 × μ

 ∴ μ = (174.67 - 80)/171.74

= 0.55

Posted Date: 1/29/2013 2:42:24 AM | Location : United States







Related Discussions:- Compute the coefficient of friction at block, Assignment Help, Ask Question on Compute the coefficient of friction at block, Get Answer, Expert's Help, Compute the coefficient of friction at block Discussions

Write discussion on Compute the coefficient of friction at block
Your posts are moderated
Related Questions

Tension in the string and acceleration of body: The two bodies weighing 300N and 450N are hung to two ends of the rope passing over an ideal pulley as shown in the figure giv

Keywords related to railway line: Railway Station : A facility along a railway line where trains stop and passengers are serviced, and cargo is handled. Platform : A fa

Details of rolling process,Different rolling methods,

engineering dynamics problems of kinetics of particle


A projectile is fired with a velocity u at the entrance A of a horizontal tunnel of length L and height H. Determine the minimum value of u and the corresponding angle \theta for w

mostly what aspects trouble mechanical engineers?


Determine the springs needed to absorb the energy: A vehicle weighing 28 kN and running at 2.5 m/sec is to be brought to rest by a buffer springs. Determine the number of spri