Silicon sample is 2.5 cm long and has a cross-sectional area of 0.1cm^2 . the silicon has an impurity concentration of nd=2×10^15 cm^-3 and na=0.
(a) calculate the thermal-equilibrium values of electron and hole concentrations
(b) calculate the conductivity and electron mobility if the resistance of the sample is measured to be 70 ω.
(c) if 2v bias is applied alone the length. calculate the drift current and current density.

Who was the first scientist to measure speed as distance over time?

Asubject in a clinical research trial experiences a serious, unanticipated adverse drug experience. how should the investigator proceed, with respect to the irb, after the discovery of the adverse event occurrence? a. do not report the adverse drug experience to the irb since it is a common adverse experience.b. report the adverse drug experience to the irb only if there are several other occurrences.c. report the adverse drug experience as part of the continuing review report.d. report the adverse drug experience in a timely manner, in keeping with the irb's policies and procedures, using the forms or the mechanism provided by the irb.

Awater balloon launcher uses an elastic band with a spring constant of 115 n/m to use thee launcher you stretch thee band back with a balloon n it the water balloons have a mass of 1.3 kg a) if you stretch the band by 0.8 m, what elastic force will the band exert? b) with the band stretched 0.8 m, how much elastic potential energy is stored in the spring? c) if you release the band, it pushes forward. what is the kinetic energy of the balloon when it reaches the natural length of the band? d) what is the speed of the balloon when it reaches the natural length of the band?