## [SOLVED] Electric Fields Physics

a) Without doing any calculation, write down the approximate electric field (magnitude &direction) a distance d from the origin, assuming that d>>a. Make sure to justify your answer.b) Calculate the electric potential at a point P on the z axis, a distance z from the center of the object. Assume that the potential at infinity is zero. You dont need to evaluate any integrals you run into. Just leave the answer in integral form.c) Calculate the electric field (magnitude and direction) at a point P on the z axis, a distance z from the center of the ring. You dont need to evaluate any integrals you run into. Just leave the answer in integral form.d) Take the limit z>>a to show that your electric field reproduces your answer from part (a). [Hint: It helps to write your expression in terms of the small dimensionless parameter a/z.]

## [SOLVED] Physics Electric Forces

a) Does q b feel any electric forces from q c , q d , or any of the surface charges induced by q c or q d ? Explain your reasoning.b) How much total charge accumulates on each of the two surfaces of the cavities? How much total charge accumulates on the exterior surface? Explain your reasoningc) Are the charge densities induced on the cavity surfaces uniform? Explain your reasoning.d) If r is very large compared to the radius of the conductor, what is the approximate magnitude of the force felt on q d ?

## [SOLVED] Microstructure Changes

The phase diagram for the Al – Si system (the basis of aluminium casting alloys) is shown in Figure 1. Explain what is happening when the alloy Al  30 wt % of Si is cooled from 900 ? to room temperature. You need to consider phasetransformation, microstructure changes, temperatures, and composition.(6 marks)Figure 1: Phase Diagram of Al – Si binary system(ii) You have been asked to calculate the critical nucleus radius, r* and the activation free energy ?????? for the solidification of pure nickel if nucleation is homogenous. The latent heat of fusion and surface energy of nickel are given as -2.53 x 109 J/m3 and 0.250 J/m2 respectively. The supercooling curve value for nickel is 319 ?. The melting temperature of nickel is 1455 ?.(4 marks)

## [SOLVED] Moving Balloons

1. Moving balloons:In the picture below, the balloons on the left and middle are held in place. The right balloon is free to move.Is it possible to add positives or negatives on the free balloon that would make it moveto the left ( ß )? ­­­­­___________If so, then draw positives or negatives on the balloon that would make it move, and explain why you think it would work? ­­­­­­­­­

## [SOLVED] Photocatalysis Of TiO2 Material

Please help me write a report focusing on “photocatalysis of TiO2 material”. Most of the papers regarding this topic can be found online.Requirement:- 8 to 10 pages long- Does not have to be strictly plagiarism free (you can pick certain ideas from certain paper and lightly paraphrase their idea. You can just copy paste their images if they have any)

## [SOLVED] Crystal Structure

Numerical simulationFinal report: Comparison simulation data of Si4N3 dielectric material(doi: 10.17188/1197656)I. IntroductionSilicon nitride (Si3N4) is a non-metallic compound composed of silicon and nitrogen. This material is interesting because of its durability, electrical insulation, high thermal stability and high acid resistance that widely used in microelectronics and micro-surface machining technologies.The micro-bolometer devices were fabricated at nano and energy center (NEC) of Vietnam national university (VNU) used Si3N4 shut as a supporting layer for the suspending structure and in absorption infrared radiation (IR) packet. The fabrication method used plasma enhanced chemical vapour deposition (PECVD) system that require high vacuum. The optimization of IR absorption packet by experimental is extremely expensive. Thus, the properties of Si3N4 crystal structure need to investigate by simulation and compare to experiment data.

## [SOLVED] High Absorption Effect

Question 1: In the “Introduction” section (second paragraph), they claim that strong linear absorption in the OPA technique makes this only usable for 2D scanning and the absence of linear absorption in TPA technique and local non-linear absorption makes this technique applicable for 3D scanning. Please explain and elaborate this idea with graph and/or equation.Question 2: In the “Working principle of LOPA microscopy” section, they wrote: “The intensity increases nonlinearly and reaches a maximum value at the focal plane ” (line 2 and 3). Please explain and elaborate this idea with drawing and/or equation.Question 3: In the “Working principle of LOPA microscopy” section, from line 1 to 6 at page 4, they imply that the high absorption of OPA decreases the intensity of light and this is a disadvantage of OPA technique and it hinders the the OPA technique from achieving what the TPA technique can do (being able to give off light with high intensity and get photo induced effect). However, at line 8 to 11 they claimed that the strong linear absorption of OPA technique can also get photo induced effect ? Can you elaborate on this idea ? i think im misunderstanding somethingQuestion 4: In the “Working principle of LOPA microscopy” section, paragraph 2 (from line 12 page 4). They are explaining on how they get low absorption effect with OPA. I don’t understand this at all. Can you explain this with drawing and/or equation ? thank you.Question 5: In the “Working principle of LOPA microscopy” section, paragraph 2, line 7 to 9 they wrote ” Although the absorption is ultra weak, the effective photo induced effect in focusing region is therefore comparable to that obtained by a laser beam with a high absorption effect”. I do not understand this point at all because i thought the whole point of this is making OPA having low absorption like the TPA technique so this OPA technique can do what the TPA technique can too. Why are they speaking of the “high absorption effect” as an advantage now ? What am i misunderstanding

## [SOLVED] Nuclear Energy

1. Using Equation 4.4, show that d represents the mean distance neutrons travel before being absorbed.25. If you were located 100 km from a 1 GW nuclear power plant, what would the neutrino flux be at your location? Assume that a 1 GW nuclear power plant releases 1021 neutrinos per second and you present a 1 m2 surface to the neutrino flu