Which of the following is(are) the reason(s) metals are good conductors of heat and electricity? Select all that apply

The question is incomplete and the options are not given but here are the options.

a. Metals can absorb more heat flow than other elements before damage occurs.

b. Particles of metallic structure begin to vibrate faster as they absorb energy.

c. Metals have a larger number of freely moving electrons.

d.Metals have high densities.

e. Metals have high melting points.

The correct options are c,d and e.

c. Metals have a larger number of freely moving electrons.

d.Metals have high densities.

e. Metals have high melting points.

The correct options are c,d and e.

Explanation:

Metals are real good conductor of heat because of the following;

Metals have larger number of freely moving electrons and these electrons move in random motion that is they are not stable, they from from place to place. Current generated in a direction is destroyed by current produced in another direction also.

Metals have high densities which is because their crystal lattice are packed very tight in the metallic structure making the metal bond to be stronger and conduct heat.

Metals have high melting point because that have a very strong metallic bond and this bond require a lot of energy to break, therefore making it to conduct heat and electricity.

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.