100%(1)1 out of 1 people found this document helpful
This preview shows page 11 - 13 out of 13 pages.
32.Parallel Plate.Consider an isolated vacuum-filled parallel-plate capacitor with chargeQand capacitanceC. What is thechangein the electric potential energy of the capacitor ifits separation distance is increased fromdto3d?2Q2Q21Q2A.4QCB.2CC.CD.2C33.Power.What is the total rate of electrical energy dissipa-tion of the resistors in the given circuit?34.Drift Velocity.A conductor with diameterDcarries a currentI, with positive chargecarriers+qand carrier densityn. If the diameter were increased by a factor of 3, keeping+qandnconstant, how should the drift velocity change to maintainI?35.
Alpha.The temperature coefficient of resistivityαof a certain Ohmic material is defined asthe ratio of the fractional change in resistivityΔρ/ρ0to the absolute change in temperatureΔT. Given the resistivity data below for three conductors X, Y, and Z, which among thechoices is the correct order according toincreasingα?A – 11
First Long ExamSecond Semester, AY 2014–2015Physics 72ConductorResistivity (10-8Ω m) atT= 20◦CResistivity (10-8Ω m) atT= 50◦CX100120Y50100Z20025036.Across the Universe.Which of the following statements is/areALWAYS TRUE?I. The I-V curve of a nonohmic material is linear.II. The I-V curve of an ohmic material is increasing.III. The I-V curve of an ohmic material is logarithmic.A. II onlyB. I and III onlyC. II and III onlyD. I, II and III37.Resistivity.A cylindrical conductor has resistivityρ, lengthLand radiusr. By how muchshouldLbe increased/decreased if we were to quadruple the cylindrical conductor’s radiusin order to maintain its resistance?38.Power Dissipation.A50.0 Ωbulb is connected across the terminals of a10.0 Vbatterywith an internal resistance of5.00 Ω. What percentage of the power of the battery is dissi-pated across the internal resistance and hence is not available to the bulb?For the next two items, consider the circuit shown.39.Current.What is the currentI1?
First Long ExamSecond Semester, AY 2014–2015Physics 72