The repeating pattern of a minerals particles in a solid is called

Crystal structure

Explanation:

The repeated pattern of similar particles in a material is called crystal. Crystal structure is the largest constituent unit of a solid matter.

The fundamental identity of a crystal structure is a unit cell that is formed by the arrangement of atoms or ions in a particular manner. A crystal is defined as a regular, long-ranged repeated arrangement of unit cells.

Crystal have a sharp melting and boiling point and they give a sharp edge on being cut with a knife.

a) E = 2.30×10^6N/C

Direction =+E . It will point radically outward

b)E = -3.3×10^5NC^-1

Direction =- E,it will point radically inwards

Explanation:

Magnitude E at 4.7cm= 0.047m

E= wavelength 1/2×3.142×rEo

E= (6.0×10^-6)/2×3.142×0.047×(8.85×10^-12)

E= (6.0×10^-6)/(2.6×10^-12)

E= 2.30×10^6N/C

Direction= +E shows it will point radically outward.

b) Magnitude E at 8.1cm=0.081

E= (wavelength 1+ wavelength 2) / 2×3.142rEo

E= [(6.0×10^-6)-(7.5×10^-6)]/(2×3.142×0.081×(8.84×10^-12)

E= -(1.5×10^-6)/(4.5×10^-11)

E= -3.3×10^5N/C

Direction =I-A it will point inwards