Metal atoms have outer electrons which are not tied to any one atom. These electrons can move freely within the structure of a metal when an electric current is applied. There are no such free electrons in covalent or ionic solids, so electrons can't flow through them - they are non-conductors.
In a shorter term - no
solution:
You need to find the frequency, and they have already given you the wavelength. And since you already know the speed of light, you can use formula (2) to answer this problem. Remember to convert the nano meters to meters because the speed of light is in meters. 
Wax is definitely susceptible to heat and with the application of heat such as burning a candle, the solid wax gets converted into a liquid. This fact can be used to remove ear wax also actually using hollow candles that will melt the ear wax and allow it to be drained out of the ear.
Answer:
D. The frictional force overcomes the force that binds the electrons to the atoms, enabling the electrons to move elsewhere
Explanation:
Neutral objects becomes charged by rubbing them together due to the frictional force which overcomes the attractive force holding electrons together in an atom.
Friction is the resistance to flow or movement. When we rub bodies together, the movement of electrons becomes inhibited and this can cause an orbital electron loosely held in an atom to be pulled off as the force of friction increases. This mechanism would result in a body losing electron and another readily gaining that electron as they interact. The loss and gain of electrons causes a neutral body to become charged.
