7) Shown below are six segments of wires that are carrying electric currents. All of these segments have the same length and the same diameter, but the wires are made of different materials so they have different resistances. The currents flowing in these segments also vary. Specific values for each of these properties are given in the figures. Rank these situations from highest to lowest on the basis of the net electric charge on each segment, i.e., on the basis of the difference between the number of positive and negative charges in the wire segment. Put first the situation that has the greatest net charge, and put last the situation with the smallest net charge, i.e., the smallest difference between the number of positive and negative charges.

The wires shown are all made of the same material; the length and radius of each wire are noted. Rank in order, from largest to smallest, the resistances R1 to R5 of these wires. Explain.

Discussion: Ohm's Law describes the relationship between the resistance (R) of a wire, the roltage drop across it (V), and current through it (D): V = RI (1) Applying a known current to a wire and measuring the voltage across it will lt you determine the resistance of the wire by solving equation 1: R =, (2) The resistance of a partieular element depends on its geometry, the resistivity and the temperature. Resistivity is the tendency of the material to behave as a resistor and is an inherent property of a material, in the same sense that density or thermal expansion are inherent properties. Materials with lower resistivity, like copper, are good conductors of electricity and widely used in eireuit components while those with larger resistivity, like rubber, are used as insulators. For a wire with length (L), cross-sectional area (A), and made from a material with resistiity (p) the resistance (R) will be given by the following equation: R= L (3) In case that the geometry (length and…

kenney works at an iron manufacturing plant. he make a piece of iron that has a resistivity of: 1.0 x 10-7-m this iron piece is in the shape of a truncated cone. help kenney calculate the resistance between the two circular ends of the cone. 2.00 cm 20.0 cm 4.00 cm

6. A copper wire of cross-sectional area 2.0 x 10-6 m2 and length 4.0 m has a current of 2.0 A uniformly distributed across the area. (a) What is the magnitude of the electric field along the wire? (b) How much electrical energy is transferred to thermal energy in 30 minutes?