Determine the flexural capacity, ÏMn for the singly reinforced rectangular beams having the following properties. Use strength reduction factors from ACI Code. Use beam 1 as a reference, identify the best way to increase the flexural capacity of a reinforced concrete beam and discuss.

Beam No. b (in.) d (in.) Bars f_c (psi) f_y (psi)
1 12 22 3 No. 7 4,000 60,000
2 12 22 2 No. 9 plus 1 No. 8 4,000 60,000
3 12 22 3 No. 7 4,000 80,000
4 12 22 3 No. 7 6,000 60,000
5 12 33 3 No. 7 4,000 60,000

The y form of iron is known as: a) ferrite b) cementite c) perlite d) austenite

Ajournal bearing has a journal diameter of 3.250 in with a unilateral tolerance of 20.003 in. the bushing bore has a diameter of 3.256 in and a unilateral tolerance of 0.004 in. the bushing is 2.8 in long and supports a 700-lbf load. the journal speed is 900 rev/min. find the minimum oil film thickness and the maximum film pressure for both sae 20 and sae 20w-30 lubricants, for the tightest assembly if the operating film temperature is 160°f. a computer code is appropriate for solving this problem.

The filament of an incandescent lamp has a temperature of 2000k. calculate the fraction of radiation emitted in the visible light band if the filament is approximated as blackbody