- #1

Femme_physics

Gold Member

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The X axis in the first diagram is in line with the surface, but when you isolate BC it doesn't have to be. Notice how when we isolate BC our angles our different. Who's correct?

http://img192.imageshack.us/img192/236/objectthingy.jpg

The object is in static equilibrium.

Static Coeffecient between the box and surface: 0.3

Weight of box: 500 [N]

Measurements in mm

Joints are smooth pin.

Do the calculations as the box about to descend down the surface

Ignore the weight of lever ACCalculate:

Force at AB

The moment around C, acting on the arm BC

I got Fab correct (in the solution manual they call it "S"). However, we have our differences at beam BC about the angle, which I'd like you to help me resolve. The manual thinks it's 20 degrees, I think it's 50 degrees. Attached my attempt and the solution manual's.

## Homework Statement

http://img192.imageshack.us/img192/236/objectthingy.jpg

The object is in static equilibrium.

Static Coeffecient between the box and surface: 0.3

Weight of box: 500 [N]

Measurements in mm

Joints are smooth pin.

Do the calculations as the box about to descend down the surface

Ignore the weight of lever ACCalculate:

Force at AB

The moment around C, acting on the arm BC

## The Attempt at a Solution

I got Fab correct (in the solution manual they call it "S"). However, we have our differences at beam BC about the angle, which I'd like you to help me resolve. The manual thinks it's 20 degrees, I think it's 50 degrees. Attached my attempt and the solution manual's.

#### Attachments

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