A solenoid is created by wrapping a L = 85 m long wire around a hollow tube of diameter D = 1.5 cm. The wire diameter is d = 1.1 mm. The solenoid wire is then connected to a power supply so that a current of I = 4.5 A flows through the wire.

A. Write an expression for the number of turns, N, in the solenoid. You do not need to take into account the diameter of the wire in this calculation.

B. Calculate the number of turns, N, in the solenoid.

C. Write an expression for the length of the solenoid, (L2), in terms of the hollow tube D, the length of the wire L, and the diameter of the wire d. Assume it is constructed by using only 1 layer of loops (note that most solenoids are actually constructed using many layers to maximize magnetic field density).

D. Calculate the length of the solenoid, (L2), in meters.

E. Calculate the magnitude of the magnetic field at the center of the solenoid, in Tesla.

To understand the behavior of the electric field at the surface of a conductor, and its relationship to surface charge on the conductor. a conductor is placed in an external electrostatic field. the external field is uniform before the conductor is placed within it. the conductor is completely isolated from any source of current or charge. part a: which of the following describes the electric field inside this conductor? it is in the same direction as the original external field.it is in the opposite direction from that of the original external field.it has a direction determined entirely by the charge on its surface.it is always zero. part b: the charge density inside the conductor is: 0non-zero; but uniformnon-zero; non-uniforminfinite part c: assume that at some point just outside the surface of the conductor, the electric field has magnitude e and is directed toward the surface of the conductor. what is the charge density η on the surface of the conductor at that point? express your answer in terms of e and ϵ0