Is current density a vector or a scalar? Express its relation with electric field.

Is current density a vector or a scalar quantity ? Deduce the relation between current density and potential difference across a current carrying conductor of length l, area of cross-section A, and number density of free electrons n. How does the current density, in a conductor vary with (a) increases in potential gradient ? (b) increase in temperature? ( c) increase in length? (d) increase in area of cross-section? (Assume that the other factors remain constant in each case).

What is intesity of electromagnetic wave? Give its relation in terms of electric field E and magnetic field B

Is electric current a vector or scalar quantity ? Explain

What is intensityof electromagnetic wave? Give Its relation in terms of electric field E and magnetic field B

Vectors And Scalars

a. A steady current flows in a metallic conductor of non - uniform cross section. State which of the quantities i.e., current density, electric field, and drift velocity, current density, electric field, and drift velcoity remain constant? b. A steady current passes through a cylindrical conductor. Is there an electorn field inside the conductor?

Choose the correct statements :- (a) The density of electric lines of force at a point is independent of the magnitude of electric intensity vector E at that point (b) The density of electric lines of force at a point is proportional to the magnitude of electric intensity vector E at that point (c ) Actually, the electric field lines do not exist. This is just a graphical description of the electric field (d) Actually, the electric field lines exist