8:58 A Dr Irfan Yesterday, 8:16 AM 858 42 B/s ASSIGNMENT 2 PHY-4850 ⚫Q1. Write the equation for the total drift current density. Is the linear relationship between drift current density and electric field always valid? Why or why not. ⚫Q2. Define electron and hole mobility. What is the unit of mobility? ⚫Q3. Explain the temperature dependence of mobility. Why is the carrier mobility a function of the ionized impurity concentrations? Q4. Define conductivity. Define resistivity. What are the units of conductivity and resistivity? •5. Sketch the drift velocity of electrons in silicon versus electric filed. Repeat for GaAs. ⚫Q6. Write the equations for the diffusion current densities of electrons and holes.

a isothermal plasma is confined between the planes x=+-a in a magnetic field B=Bo Z. Jensity distribution is A) Derive an expression for the electron diamagnetic drift velocity vpe as a function of x. B) Draw a diagram showing the density profile and the direction of vDe on both sides of midplane if B is out of the paper. C) Evaluate vp, at x=a/2 if B=0.5T, KT,=10ev and a=7cm.

Equation1: Q(t)=CVcap(t) Equation 2: Qcharging(t)=CV(1−e^(−t/RC)) 1. Combine equations 1 and 2 to create an equation capable of finding the time-dependent voltage across a charging capacitor. Equation 3: I(t)≡(dQ(t))/(dt) 2. Combine equations 2 and 3 to create an equation capable of finding the time-dependent current across a charging capacitor.

How did they get this answer 3.3,2.7 cm

Who manufacturing Evm machine?

16

Q2: A Si bar 0.1 cm long and 100um2 in cross sectional area is doped with 1017 cm-3 phosphor. Find the current at 300 k with 10v applied cm? voltage. Hn = 700 (Ans. 1.12mA). v.S

5. An electron orbiting an atomic nucleus forms its own kind of current loop. For a hydrogen atom in the lowest energy state, a single electron orbits the nucleus with a radius of 52.9 pm (5.29 × 10-11 nm) and a speed of about 2.2 x 106 m/s. X Z (a) Conventional current measures the amount of charge passing a certain point per unit time: I = In this case, Qis the electron charge, and At is the time it takes the electron to complete one full orbit. Using this information, what is the magnitude of the conventional current in the hydrogen atom? Answer: I = 1.05 mA. (b) What is the magnetic field (both magnitude and direction) at a distance of 5.29 nm along the axis of the atom, at the point indicated? Answer: -1.25 × 10-5 T 2

a 46 ll 54% O 12:06 D'bongs 1 minute ago 70 Chapter 2. Bectrotatics ray tube (ie,a conventional selevision picture tube). If a charge density p, is moving at velocity u, the convection current density is J-pu (2.77) Drill 2.23 A 4.00-mm-diameter columnar beam of electrons with charge density 0.200 Cim moves with velocity u -6.00 x 10 m/s. Determine the current, (Answer: 15.I nA) Conduction current density involves the movement of electrons through conductive media in response to an applied electric field. It is given by the point form of Ohn's lan, J-oE (2.78) Suppose che

We want to find how much charge is on theelectrons in a nickel coin. Follow this method.A nickel coin has a mass of about 5.5 g.Find the number of atoms in a nickel coin.Each mole (6.02 × 1023 atoms) has a mass ofabout 57.9 g.1. 4.89516 × 10222. 4.68685 × 10223. 4.5827 × 10224. 4.791 × 10225. 5.10346 × 10226. 4.47855 × 10227. 4.37439 × 10228. 5.62422 × 10229. 5.71848 × 102210. 5.79244 × 1022Answer in units of atoms. Part Two ( ALL PARTS CORRELATE TO EACHOTHER) Find the number of electrons in the coin. Eachnickel atom has 28 electrons/atom. 1. 1.42897 × 10242. 1.16651 × 10243. 1.45813 × 10244. 1.31232 × 10245. 1.60117 × 10246. 1.67981 × 10247. 1.73773 × 10248. 1.28316 × 10249. 1.34148 × 102410. 1.22483 × 1024Answer in units of electrons Part Three Find the magnitude of the charge of all theseelectrons. 1. 2.33619 × 1052. 2.10257 × 1053. 1.86895 × 1054. 1.9624 × 1055. 2.69135 × 1056. 2.56537 × 1057. 2.38291 × 1058. 2.28946 × 1059. 2.52308 × 10510. 2.42544 × 105Answer in units of C.