Semi-conductors are made by adding impurities to silicon wafers. The silicon wafer is 0.1 cm thick and originally contains one phosphorus (P) atom for every 10 million Si atoms. After the diffusion process, there are 292 phosphorus atoms for every 10 million Si atoms at the top surface and the concentration at the bottom surface did not change. Calculate the concentration gradient in atomic percent/cm Note: The lattice constant of diamond cubic silicon is 5.4307 angstroms with 8 atoms per cell. The answer should have 3 decimals of accuracy.

Aflywheel accelerates for 5 seconds at 2 rad/s2 from a speed of 20 rpm. determine the total number of revolutions of the flywheel during the period of its acceleration. a.5.65 b.8.43 c. 723 d.6.86

In general, how do thermosetting plastics compare to thermoplastics in mechanical and physical properties?

Afoot bridge is made as a simple deck, 4 m long, with a cross section 2 m (wide) and 20 cm thick, and made of wood. the deck is supported at the two ends. the maximum load allowable on the bridge is 10 tons, provided it is uniformly distributed on the deck. to sense this load, a strain gauge is placed at the center of the bridge and its resistance is monitored. if the sensor has a nominal resistance of 350 s2 and a gauge factor of 3.6, what is the reading of the strain gauge at maximum load? the modulus of elasticity for the wood used in the construction is 10 gpa.