Answer to Question #264943 in Electrical Engineering for sam

Question

a) Find the total amount of electrons embedded within the sphere with r = 6 m, given that the ρv = ‒ 14/(r sin 𝜃) nC/m3

b) A standard good quality USB fast charging wire should capable to deliver a maximum power of 100W. Ali has bought a cheap USB wire from RM2 shop. He found that the wire with length of 2.0 m only capable to charge his mobile phone, at 5V 2A. As a technologist and scored A+ in the subject of Electromagnetic Theory, Ali knows that in order to fast charge his phone, he has to replace the low current density cheap wire. Ali saw that Mr.DIM shop selling the single core wire come with specification of 282.8 nΩm and 1.2 mm diameter. If he wishes to rebuild a same length of USB-C wire which is capable to deliver a fast charging current of 4.5A,

(i) what is the minimum electric current density of the desired wire?

(ii) is the wire that Ali saw in Mr.DIM shop suitable for this wire rebuild project? Justify your answer with mathematical prove with assuming the phone impedance is 1Ω.

Answer 1

a.

b