Two solenoids, A and B, are wound using equal lengths of the same ...

[cherise1989]

Two solenoids, A and B, are wound using equal lengths of the same kind of wire. The length of the axis of each solenoid is large compared with its diameter. The axial length of A is twice as large as that of B, and A has twice as many turns as B. What is the ratio of the inductance of solenoid A to that of solenoid B?
  1.4
  2.2
  3.1
  4.1/2
  5.1/4

Question 2

Discuss the crystalline structure of minerals.

[yuyiding]

Answer to Question 1

4

Answer to Question 2

A crystalline substance has a definite internal structure such that the atoms are in
specific proportions and are arranged in an orderly geometric pattern. Under ideal
conditions of crystal growth, perfect crystal faces will form. Although the size of a
crystal may vary, the angle between faces of a specific mineral will be the same.
Substances that when crystallizing become solid without a definite internal structure
are called amorphous.

[cherise1989]

Gracias!

[parshano]

Thanks for the timely response, appreciate it