Posted by **Kallie** on Saturday, June 9, 2012 at 12:06pm.

The mass of the sign shown is 28.5 kg. Find the weight supported by (a) the left support and (b) the right support.

Between the left and right support is 0.900m and from the right support to the end of the sign is 0.300m.

------------------------------

| | --------> (0.900m)|| --->(0.300m)

I got answers: a. 111.1 and b. 186.2 but I'm not sure if they're correct. Can someone please help?

- Physics -
**Elena**, Saturday, June 9, 2012 at 6:15pm
Weight of the sign is W = mg = 28.5kg•9.8m/s² = 297.3N

The sum the moments around the left bottom of the sign.

Clockwise moment Mcw = 297.3N • (1.2m/2) = 167.6 N•m

Counterclockwise moment Mccw = F•0.9m

That is, the cw rotation of the sign about the left corner is resisted by a support force.

F = 167.6N•m / 0.9m = 186.2N ← in the right column

The left support can be determined in a similar fashion, or simply by noting that it must support the remaining vertical force:

Left F = W - Fr = 297.3N - 186.2N = 111.1N ← left support

- Physics -
**Austin**, Tuesday, November 4, 2014 at 1:52pm
28.5x9.80 = 279.3 not 297.3.

therefore the left support would equal 93.1 not 11.1

## Answer this Question

## Related Questions

- Physics - A 5.00 m long rigid beam with a mass of 200.0 kg is supported at each ...
- Physics - Suppose a crate of mass 2.8 kg is placed on the plank in the figure ...
- physics - A bridge of length 22 m and mass 1.5 × 105 kg is supported at each end...
- physics - A bridge is supported at both ends (500m between supports). A Car (250...
- Physics - A uniform plank of length 5.5 m and weight 219 N rests horizontally on...
- physics - A 3.0-m-long rigid beam with a mass 130 kg is supported at each end. ...
- PHYSICS - A woman whose weight is 530 Newtons is standing on the outer edge (...
- physics - A gymnast with mass m1 = 47 kg is on a balance beam that sits on (but ...
- physics - A 3.0 m long rigid beam with a mass of 100 kg is supported at each end...
- Physics - A woman who weighs 500N stands on an 8.0-m-long board that weighs 100N...