Concept explainers
CALC A material of resistivity ρ is formed into a solid, truncated cone of height h and radii r1 and r2 at either end (Fig. P25.59). (a) Calculate the resistance of the cone between the two flat end faces. (Hint: Imagine slicing the cone into very many thin disks, and calculate the resistance of one such disk.) (b) Show that your result agrees with Eq. (25.10) when r1 = r2.
Figure P25.59
Learn your wayIncludes step-by-step video
Chapter 25 Solutions
University Physics with Modern Physics Plus Mastering Physics with eText -- Access Card Package (14th Edition)
Additional Science Textbook Solutions
Lecture- Tutorials for Introductory Astronomy
Physics for Scientists and Engineers: A Strategic Approach, Vol. 1 (Chs 1-21) (4th Edition)
College Physics
University Physics (14th Edition)
Physics: Principles with Applications
Essential University Physics: Volume 2 (3rd Edition)
- You are working with an oceanographer who is studying how the ion concentration in seawater depends on depth. She shows you the device that she uses to measure the resistivity of water from a boat. It consists of a pair of concentric metallic cylinders at the end of a cable (as shown). Seawater flows freely between the two cylindrical shells. She makes a measurement by lowering the device into the water and applying a potential difference ΔV between the inner and outer cylinders. This produces an outward radial current I in the seawater between the shells. She shows you the current and voltage data for the water at a particular depth and is then called away to answer a long call on her cellphone about a laboratory issue back on the mainland. As she leaves, she says, “Have the resistivity of the water calculated when I get back.” She forgot to show you any tables or formulas to use to determine the resistivity, so you are on your own. Quick! Find an expression for the resistivity in…arrow_forwardWhale and Kanmuro are two islands located in the Chimera archipelago. These two are separated by a distance of 20 miles. A power link is to be established between them. The power link delivers a maximum power of 600 MW at full capacity with an operating voltage of 500 kV. Solve for the resistivity of the cable, assuming a conductor diameter of 1.5 cm. Express your answer in p0-m.arrow_forwardA capacitor with a capacitance of 3.5 μF is initially uncharged. It is connected in series with a switch of negligible resistance, a resistor with a resistance of 19 kΩ, and a battery that has a potential difference of 170 V. What is the charge Q, in microcoulombs, on the capacitor when the current in the resistor equals one half its maximum value.arrow_forward
- Asap plzzarrow_forwardCopper has a work function of 4.70 eV, a resistivity of 1.7 x10-8 Ω ∙ m, and a temperature coefficient of 3.9 x10 -3 °C -1. Suppose you have a cylindrical wire of length 1.5 m and diameter 0.40 cm connected to a variable power source.a) Draw a clear physics diagram b) At what temperature would the wire have 2 times the resistance that it has at 20 °C?c) What is the peak wavelength of radiation emitted by a wire of thistemperature?d) If light at only the wavelength found above were shone onto a copper plate, what would be the maximum kinetic energy of the ejected electrons?arrow_forwardA material is formed into a long rod with a square cross-section 0.50 cm on each side. When a 100 V voltage is applied across a 20 m length of the rod, a 5.0 A current is carried. a) What is the resistivity of the material? ρ = _______ Ω m b) Is the material a conductor, an insulator, or a semiconductor?arrow_forward
- A 60 W lightbulb has a resistance of 240 Ω. At the operating temperature of the tungsten filament, its resistivity is approximately 5.0 x 10-7 Ω • m. If the wire used to make the filament is 0.040 mm in diameter (a typical value). As described above the length of a 60 W, 240 Ω lightbulb filament was calculated to be 60 cm.a. If the potential difference across the filament is 120 V, what is the strength of the electric field inside the filament?b. Suppose the length of the bulb’s filament were doubled without changing its diameter or the potential difference across it. What would the electric field strength be in this case?c. Remembering that the current in the filament is proportional to the electric field, what is the current in the filament following the doubling of its length?d. What is the resistance of the filament following the doubling of its length?arrow_forwardProblem 4: A solid conical frustum has a length L = 14 cm, an initial radius R1 = 6.5 mm and a final radius R2 = 11 mm. The material that it is made from has a resistivity p = 2.4 × 10-5 Q m. L R2 R1 Part (a) Integrate over the length of the frustum to write an equation for the resistance of the frustum in terms of L, R1, R2, and p. Expression : R = Select from the variables below to write your expression. Note that all variables may not be required. a, B, n, p, 0, B, d, dx, g, L, m, R1, R2, t, x Part (b) Calculate the resistance for the frustum in units of ohms. Numeric : A numeric value is expected and not an expression. R =arrow_forwardA coaxial cable consists of two concentric cylindrical conductors. The region between the conductors is completely filled with polyethylene plastic as shown in the figure. The radius of the inner conductor is a= 0.6 cm, the radius of the outer conductor is b = 1.8 cm, and the length is L= 30 cm. The resistivity of the plastic is p= 1013 n. m Calculate the resistance of the plastic between the two conductors. Inner Outer conductor conductorarrow_forward
- A disk of thickness d and radius b has a hole at the center of radius d. If you know that the electrical conductivity of the disk material is a. Find an equation to calculate the electrical resistance R between the central hole and the edge of the disk?arrow_forwardTwo conductors are made of the same material and have the same length. Con- ductor A is a solid wire of diameter 1.0 mm. Conductor B is a hollow tube of outside diameter 2.0 mm and inside diameter 1.0 mm. What is the resistance ratio RA/RB, mea- sured between their ends?arrow_forwardThe rod given in the figure is made up of two different materials. Both have square crosssections of 3 mm side. The resistivity of the first material is 4 x 10-3 Ω.m and it is 25 cmlong while second material has resistivity of 5 x 10-3 Ω.m and is of 70 cm long. What is theresistivity of rod between its ends?arrow_forward
- Principles of Physics: A Calculus-Based TextPhysicsISBN:9781133104261Author:Raymond A. Serway, John W. JewettPublisher:Cengage Learning