First of all, looks like your teacher is indeed pretty horrible. Secondly, the constraints to consider would be proper weight distribution, methods to minimize excessive motion of the building structure, and quantities such as volume and density, which would help in determining the optimal structure. Keeping the frequency of oscillation for a building low in case of an earthquake or natural disaster would also be a priority.
Answer:
They would be pointing in the same direction
Explanation:
If they were facing each other then it may seem like they are pointing in different directions they would still point the same way.
(I assume that the 4 directions north-south-east-west are meant with respect to the wire seen from the top.)
We can use the right-hand rule to understand the direction of the magnetic field generated by the wire. The thumb follows the direction of the current in the wire (upward), while the other fingers give the direction of the field in every point around the wire. Seen from the top, the field has an anti-clockwise direction. Therefore, if we take a point at east with respect to the wire, in this point the field has direction south.
Answer:
Maximum permitted surface crack length is 1.29 mm
Explanation:
As per the question:
Tensile stress, 
Surface energy of magnesium oxide, SE = 
Modulus of elasticity of the material, E = 225 GPa = 
Now,
To calculate the maximum allowable surface crack length:
