A resistor is constructed of a carbon rod that has a uniform cross-sectional area of 5.00 mm². When a potential difference of 15.0 V is applied across the ends of the rod, the rod carries a current of 4.00 x 10³ A. Find (a) the resistance of the rod and (b) the rod's length.

A rear window defroster consists of a long, flat wire bonded to the inside surface of the window. When current passes through the wire, it heats up and melts ice and snow on the window. For one window the wire has a total length d = 11.6 m , a width a = 1.8 mm, and a thickness w = 0.11 mm. The resistivity of the metal is ρ = 2.6 × 10^−8Ωm. The wire is connected to the car’s 12.0 V battery. (a) What is the current flowing through the wire? (b) What is the power of the window defroster?

There is a potential difference of 1.7 V between the ends of a 10 cm long graphite rod that has a cross-sectional area of 1.7 mm2. The resistivity of graphite is 7.5  10-6 Ω-m. (a) Find the resistance of the rod.\ (b) Find the current. (c) Find the electric field inside the rod.

A wire 3.43 m long and 6.38 mm in diameter has a resistance of 11.6 mQ. A potential difference of 17.7 V is applied between the ends. (a) What is the current in amperes in the wire? (b) What is the magnitude of the current density? (c) Calculate the resistivity of the material of which the wire is made. (a) Number Units (b) Number i Units (c) Number i Units >

Problem 1. A 50.0 m long Aluminum wire has a diameter of 0.50 mm and is at 20.0°C. If it carries a current of 0.50 mA, (a) calculate the power delivered to it? (b) If the temperature is increased to 340°C and the potential difference across the wire remains constant, what is the power delivered?

As part of a class project you are given 0.900 g of copper and asked to fabricate a wire with uniform cross-section. You use up 95% of the copper and make a wire with a resistance of 0.723 Ω. The resistivity of copper is 1.72  10-8 Ω · m and its density is 8.92  103 kg/m3. (a) What length of wire do you end up with? (m)(b) What is the diameter of the wire? (mm)

Wires A and B, having equal lengths of 41.8 m and equal diameters of 2.89 mm, are connected in series. A potential difference of 61.6 V is applied between the ends of the composite wire. The resistances are RA = 0.108 0 and Rg - 0.617 0. For wire A, what are (a) magnitude Jof the current density and (b) potential difference V? (c) Of what type material is wire A made (see the table below)? For wire B. what are (d) Jand (e) V? (f) Of what type material is B made? Resistivities of Some Materials at Room Temperature (20°C) Resistivity, p (N-m) Temperature Coefficient of Resistivity, a (K) Material Typical Metals 4.1 x 10- 1.62 x 10- 1.69 x 10- Silver 4.3 x 10- Copper Gold 4.0 x 10- 4.4 x 10- 0.002 x 10- 45 x 10- 6.5 x 10- 2.35 x 10 2.75 x 10- 4.82 x 10- 5.25 x 10- 9.68 x 10- 10.6 x 10- Aluminum Manganin Tungsten Iron Platinum 3.9 x 10- Typical Semiconductors 25 x 10 8,7 x 10- -70 x 10- Silicon, pure Silicon, n-type Silicon, p-type 2.8 x 10- Typical Insulators 10- 104 ~10M Glass Fused…