Chapter 14: Q11Q (page 578)

Make a table showing the major differences in the electric properties of plastic, salt water, and copper. Include diagrams showing polarization by an external charge.

Short Answer

Expert verified

Out of the three elements, plastic has very low conductivity, it is considered a good insulator, and copper has higher conductivity, it is an excellent conductor and is used in electrical installations. Salt water has a low conductivity, it is a bad conductor.

Step by step solution

Concept/Significance of polarization

The polarisation is defined as the dipole moment per unit volume, and it is a vector quantity. Still, induction is only a phenomenon in which charges get polarised in the opposite direction.

Determination of the major differences in the electric properties of plastic, salt water, and copper

Material	Electric property Conductivity	Electric use
copper	$τ = 59.6 s/m$	Excellent conductor
Salt water	$τ = 5 s/m$	Bad conductor
Plastic	$τ = 10^{- 13} s/m$	Insulator

The behavior of the plastic and water molecules are shown in the figure above and in the case of copper, the polarity of free electrons is higher that has this material is observed.

Thus, out of the three elements, Plastic has very low conductivity, it is considered a good insulator, and copper has higher conductivity, it is an excellent conductor and is used in electrical installations. Salt water has a low conductivity, it is a bad conductor.