Holes are being steadily injected into a region of n-type silicon (connected to other devices, the details of which are not important for this question). in the steady state, the excess-hole concentration profile shown in fig. p3.10 is established in the n-type silicon region. here "excess" means over and above the thermal-equilibrium concentration (in the absence of hole injection), denoted pn0. if nd = 1016/cm3, ni =1.5×1010/cm3, dp =12 cm2/s, and w =50 nm, find the density of the current that will flow in the x direction.

The 10-kg double wheel with radius of gyration of 125mm about o is connected to the spring of stiffness k = 600 n/m by a cord which is wrapped securely around the inner hub. if the wheel is released from rest on the incline with the spring stretched 225 mm, calculate the maximum velocity v of its center o during the ensuing motion. the wheel rolls without slipping

Acup of coffee sits on the dashboard of an automobile. the car goes around a sharp curve. even though you hold the cup still, coffee still splashes out. this can best be explained due to a) density. b) friction. c) gravity. d) inertia.

Scout feels ill one day before school. her mother puts a thermometer in her mouth and the temperature begins to climb to 100°f. what is happening between the cooler thermometer and scout's body? a) scout's body is applying a force to the particles in the thermometer. b) kinetic energy is being transferred from her mouth to the thermometer. c) potential energy is being lost by the thermometer and gained by scout's body. d) the potential energy stored in foods is converted to mechanical energy to raise the mercury in the thermometer.