Directions: The following diagrams are three sets of motor materials in different combinations. If you are going to assemble a simple electric motor, which
combination are you going to choose to make the rotation of the motor faster?
Explain briefly your answer.​

the answer is c.the valence of the atoms combine .

ok whats the question if not i cannot you i need question and need a thing to answer

answer: semi-infinite solid initially at a uniform temperature of 400 ◦c is cooled at its surface by convection. the cooling fluid at a constant temperature of 200 ◦c has a convective coefficient (ha) of 250 w/m2.k. the physical properties of the solid: k = 20 w/m.k and α = 4 * 10-5  m2/s. using δx = 0.04 m and δt = 10 s. write the finite difference equations describing the transient heat transfer of the first five δx and the temperature profile after 30 s.