Shearing Stress

Two bars, one having a circular section of radius b, the other an elliptic section with semiaxes a,b. For equal angles of twist, which bar experiences the larger shearing stress? For equal allowable shearing stresses, which one resists a larger twisting moment?

Calculate reactions of a simply supported continuous beam.

A beam is simply supported at the ends and is continuous over two spans. The left-hand span is 16 ft. and the right-hand span is 20 ft. The beam supports a uniform load of 900 plf, which includes its own weight, over the entire 36 ft. span and also a concetrated load of 8000 lb applied at a point that is 5 ft. from the left-hand end of the beam. The total bending moment at the intermediate support due to the uniform load and the concentrated load is equal to -45,820 ft-lb. The reactions at the left-hand, right-hand, and intermediate supports are?

Determine the reactions of simply supported beam to both a concentrated and uniform load.

A beam with a span of 21 ft is simply supported at the left-hand end and fixed at the right-hand end. It carries a uniform load of 800 plf, which includes its own weight, over its entire span and a concentrated load of 12,000 lb located 7 ft from the left-hand end. The total bending moment at the fixed end is equal to -81,400 ft-lb. What is the reaction at the simple support? What is the reaction at the fixed support?

Calculate bending moments, radius of gyration, axial loads, etc.

Please see the attached files for full problem descriptions.

OLED

Q1: Explain clearly the fabrication steps involved in the fabrication of Organic LED. (a full page) Q2: Compare the brightness of OLED quantitatively with semiconductor LED emitting in red, green and blue colors. (half a page)