PHYS121A_ Lab 218

3. Define drift velocity. Describe (with diagrams if appropriate) how the idea of drift velocity occurs in the Drude (classical) and Sommerfeld (Quantum mechanical) models and state any significant differences in the implications of the models for electrical transport.

University of Management and Technology, Sialkot Campus (Mid – Term Spring- 2021) Department of Physics Course Name: Medical Physics Instructor: Dr. Haroon Asghar Total Marks: 15 Time: 1 hour Q1. What is the significance of angular momentum in Bohr's atomic model? (2) Q2. What are the advantages and limitations of Gauss's law? Q3. How capacitance effects when we place page between two conductor plates. Q4. What is fundamental difference between electrostatics and magnetostatics. Q5. Two conducting plates carries surface charge density o. Find the electric field in the (2) (3) (2) Region-I, Region-II and Region-II. (3) Region-I Region-II Region-III Q6. Write down the general means by using which we can change the magnetic flux through the coil? (3) GOOD LUCK!

1. Consider a simple ionic drive. a) If the drive field is 10,00OV/m what is the force on the spacecraft from a singly ionized charge being accelerated. b) Assume the electrical length of the engine is 0.2m. Find the impulse from this charge if the charge is accelerated at a constant acceleration. (Mcharge = 2.2e-23kg) c) Find the force of one mole of nitrogen atoms through this engine. d) Find the impulse of one mole of nitrogen atoms through this engine. e) Find the electrical current and power needed to drive such a device.

3) In Millikan’s oil drop experiment an oil drop with N additional electrons and mass m is subjected to an electric field E. It is observed that the oil drop is moving downward at constant velocity v. The friction force on the electron is kv. Gravity is negligible. a) Draw a figure and show the directions of the friction force Ff and the electric force Fe. b) Find the charge q of the oil drop in terms of k, v and E. c) Find the number of electrons N on the oil drop in terms of k,v, E and e.

2. The Hall voltage across a piece of semiconductor is 5 V, the charge density of the semiconductor is 2x10" electrons per square m, the thickness of the semiconductor is 0.5 mm, and the current used to find the Hall voltage is 1 micro amp. a. What is the magnetic field? b. What happens if we keep everything else in the measurement setup the same and double the magnetic field? с. What if we doubled the current used for the measurement?

1. Describe the construction and operation of a color TV picture tube. Explain why a color tube requires a higher (EHV) dc voltage than the monochrome for equal luminance. 2. Describe with the help of a suitable diagram the operation of a color subcarrier regenerator. Show that for a series-tuned RLC circuit at resonance: (1) The total energy stored in the circuit is a constant, (2) Energy stored Energy dissipated per cycle' Qo = 27 In a crystal-controlled color subcarrier regenerator operating at 3.58 MHz, the total energy remaining in the circuit after 218 cycles of free-running oscillation is 90% of its original value. Calculate the peak value of the voltage across the capacitor at the end of the free-running cycle and estimate the Qo of the circuit.

Q2. A particle P is in rectilinear motion. The acceleration is of the form a = A cos(wt). The values of the parameters are given in Table 2. Complete the table by filling in the values in the yellow cells. P Table 2 A (constant) O (constant) t (s)| v (m/s) a = A cos(o t) (m/s²) 1 28 -36 1 1 28 13

Vm005 (b) VOS (6) Vme (d) Vm I (s) vitamikorgqs to muminima a 6 iliw Sysw diootwse AS no mo lyd beinast ei wrait terW LABORATORY 38 Oscilloscope Measurements PRE-LABORATORY ASSIGNMENT 1. Describe the components that make up the electron gun in a cathode-ray tube. 2. Describe the voltage waveform that produces a linear time scale when applied to the horizontal plates of a cathode-ray tube. 3. When the electron beam strikes the fluorescent screen, the phosphor glow that results has persistence. Approximately how long does the glow persist? 4. A function generator outputs a sine wave of f= 200 Hz. It is input to an oscilloscope set at 1 ms/DIV. How many complete cycles of the sine wave are displayed on the oscilloscope? (Hint-The period of the sine wave T is related to the frequency f of the wave by T = 1/f, and there are 10 divisions on the time display of the oscilloscope.)

2. An electron in an energy level of an atom moves in a circular path around a nucleus. The radius of the path is 1.2 x 10-11 m and the speed of the electron is 1.03 x 107 ms-1 (a) Find the centripetal acceleration of the electron. (b) Which experiences the greater force - the electron or the nucleus? (c) Find the magnitude of the force causing centripetal acceleration. (d) What is the nature of the force causing centripetal acceleration? 1.03 x67 (e) Determine the number of protons in the nucleus of the atom.

40. Which of the following provide scientific evidence for the quantization of charge? A. The charge found on single electrons and single protons B. Faraday's Law C. Milliken's Oil Drop Experiment D. The Hall Effect E. Two of the above provide evidence for the quantization of charge

1. What is the expected charge to mass ratio for an electron based on the unknown values for the charge and mass of an electron? 2. Comment on the accuracy of your results. Does your results agree with the expected charge to mass ratio for an electron

552 RADIATED EMISSIONS AND SUSCEPTIBILITY (8.1.4) A wire carrying a 1 mA current at 100 MHz is parallel to and 1 cm from an infinite, perfectly conducting ground plane as shown in Fig. P8.1.4. Deter- mine the electric field 3 m above the ground plane. [0.877 mV/m] 3m 1 mA 1 m. FIGURE P8.1.4. 1 cm

1) The electrons are tightly bound on the last orbit in these materials. A. Inductors B. semiconductors C. Insulators D. Conductors 2) What does an electrical insulator do? A. it lets eletricity flow through it in one direction. B. It lets electricity flow through it when light shines on it C. It lets electricity flow through it D. It does not let eletricity flow through it

4. MILLIKAN EXPERIMENT. An oil drop with a mass of 3.1 x10-1$kg absorbs 11 electrons, and then falls through an opening in two parallel, horizontal plates 1.8 cm apart. The upper plate is positive. a) Determine the charge absorbed by the oil drop. b) Determine the required potential difference between the plates in order for the oil drop to be suspended between the two plates.

6. The distance between the cathode and the anode is 0.02 m and the distance between the anode and the screen is 0.30 m. Compute for the time for an electron to travel: (a) between the cathode and the anode (b) between the anode and the screen.

The electronic structure of atoms and molecules may be investigated using photoelectron spectroscopy. An electron in a photoelectron spectrometer is accelerated from rest by a uniform electric field to a speed of 420 km s−1 in 10 µs. Determine the kinetic energy of the electron?     a. 8.0 x 10-20 N.m       b.  1.6 x 10-25 N.m       c. 3.8 x 10-25 N.m       d. 4..0 x 10-2 N.m

Includes a split ring commutator 1. DC motor Converts kinetic energy into the one- way flow of electrons 2. DC generator Is used to take pictures of soft tissue 3. Ammeter 4. MRI Can be powered by a battery 5. X-ray Is used in devices such as a “hover board" or a cordless drill > > > > >

2. Calculate the missing value in each of the following diagrams. a) b) 5V V= ? I=? 1= 2 A c) 6V R = ? |= 3 A

Electrons are fired through a parallel plate apparatus as shown: 10. cm 8.0 x 107 m/s | 2.0 cm If the voltage between the two plates is 350 V, calculate: b. The vertical deflection of the electron (distance); and c. The speed and direction of the electron as it leaves the two plates.

1. The reason that B field must be parrallel 2. The reason there should be no magnetic field outside

Select an appropriate statement that describes the de Broglie hypothesis. Select one: a. Just as light, electrons also have wave-like properties. b. Electrons are negatively charged particles that orbit a nucleus. c. Electrons are subatomic particles.

Problem 1 - Bio-Savart Law In an intrinsic hydrogen atom, one electron orbits the nucleus at some angular frequency fH This creates a ring with radius a and current i = âg f 1[C) 1.602x10^-19[e-)" Use the first four steps of the "patented six-step method" to find an expression for the magnetic field caused by the hydrogen atom anywhere (Robs E R).

In a CRT, electrons leave the filament as the current through the filament heats it upt.  An anode then attracts the free electrons.  According to Newton's second law of motion, the beam of electrons that emerges from the anode aperture will do this.     a.    Decelerate until they reach the fluorescent screen.     b.    Continue accelerating toward the flourescent screen.     c.     Spontaneoulsy decay into photons.     d.    Move at a constant speed toward the fluorescent screen.

Explain Faradays laws of electrolysis in details.

1. State precaution that needs to be taken when carrying out the experiment. 2. what is an electric current.

C Current Students.. S Home | Schoology Course: Student R.. etflix M maaoun4@hawkm. Aoun - Circuits Lab Simulation - 10382745 ☆ Last edit was made 11 minutes ago by Zainab Chebib dit View Insert Format Tools Add-ons Help E = = E E - E - E 12 I U Normal text Comic San. 100% * 1 . . 2 I 3 4 . 5 I 6 . 7 Section E: Concept Check 22.Why does brightness decrease when more light bulbs are added in series? 23. Based on your observations and data, what is a disadvantage of a series circuit? 24. Answer the following using the VIR table for the series circuit using question #15. is divided proportionally among each light bulb. is the same everywhere. a. In a series circuit b. In a series circuit c. In a series circuit total resistance is resistance. than any one source of Warning:If any 2 copies are the same, both students will receive a zero and it will be reported to تحذير: اي نسختين متطابقتين ، سيحصل كلا الطالبين على صفر وسيتم إبلاغ الإدارات بذلك .administration MacBook Pro * ES F8 %23 3 4 5…