Question

Circle 1, circle 2, and circle 3 have the same center and have radii, respectively, of r1 cm, r2 cm, r3 cm, where r1 < r2 < r3. Let a1 be the area of circle 1, let a2 be the area of the region within circle 2 and outside circle 1, and let a3 be the area of the region within circle 3 and outside circle 2, where all areas are in cm2. What are the values of \small \frac{a_{1}}{a_{2}} and \small \frac{a_{2}}{a_{3}} ? (1) a2 = a3 (2) a2 + a3 = 2a1

Answer 1

Answer:

Electroplating is a process that uses an electric current to reduce dissolved metal cations so that they form a thin coherent metal coating on an electrode. The term is also used for electrical oxidation of anions on to a solid substrate, as in the formation of silver chloride on silver wire to make silver/silver-chloride electrodes. Electroplating is primarily used to change the surface properties of an object (such as abrasion and wear resistance, corrosion protection, lubricity, aesthetic qualities), but may also be used to build up thickness on undersized parts or to form objects by electroforming.