Ashaft of carbon steel (aisi 1010) with a diameter of 0.1 m is heated in a gas furnace at 1200 k. the convection heat transfer coefficient is 100 w/m2. if the initial shaft temperature when entering the furnace is 300 k
a. how much time does it take for the center of the shaft to have a temperature of 800 k?
b. at the time of the answer (a) what is the difference in surface temperature and center of the axis?

Which is an example of an exothermic process?

An electron is trapped at a defect in a crystal. the defect may be modeled as a one-dimensional, rigid-walled box of width 1.00 nm. (a) sketch the wavefunctions and probability densities for the n 1 and n 2 states. (b) for the n 1 state, nd the probability of nding the electron between x1 0.15 nm and x2 0.35 nm, where x 0 is the left side of the box. (c) repeat (b) for the n 2 state. (d) calculate the energies in electron volts of the n 1 and n 2 states

Asailboat is traveling to the right when a gust of wind causes the boat to accelerate leftward at 2.5m/s2 for 4s. after the wind stops, the sailboat is traveling to the left with a velocity of 3.0m/s. assuming the acceleration from the wind is constant, what was the initial velocity of the sailboat before the gust of wind? answer using a coordinate system where rightward is positive.