Physics Answers

Question 1​​​​​​​​​​​​

 Compute the net potential energy of a simple Na⁺Cl^- pair. The equilibrium distance between the ions is 0.28nm. The potential energy due to repulsion between electrons is given by U_r= β/r⁸

Question 2

2.1​ α-Co has an hcp structure with lattice spacings of a= 2.51 A^o and c = 4.07 A^o, β Co is fcc, with a cubic lattice spacing of 3.55 A^o. What is the difference in density between the two forms?​​

2.2​ Sodium transform from bcc to hcp at about T = 23K. Assuming that the density remains fixed, and the c/ a ratio isideal, calculate the hcp lattice spacing given that the cubic lattice spacing is  a' = 4.23 A^o in the cubic phase.      ​​​

Can you apply your knowledge about physics on this type of problem when a ladder would be useful to rescue someone from an icy pond

How far can you travel into the future without aging significantly? Could this method also

apply to travels into the past?

Two spherical conducting shells of radii ra and rb are arranged concentrically and are charged to potentials Ua and Ub respectively. If Ra>Rb, find the potential at points between the shells and at points r>rb

Find the energy stored in free space for the region 2 mm ` r ` 3 mm, 0 `  ` 908, 0 ` 0 ` 908, given the potential field V 􏰁: 􏰂a􏰃 200 V; 􏰂b􏰃 300cos VX

WE 􏰁12 and write it on a differential basis,

D􏰅Edv

 Ans. 1.391 pJ; 36.7 J