Three wires of cross sectional area 3mm2, 4mm2 and 5mm2 are made up of the same material and have the same lengths, which wire has the lowest resistance? a. 5mm2 area of cross section wire O b. 4mm2 area of cross section wire c. All three wires have the same О с. resistance O d. 3mm² area of cross section wire

Three wires of cross sectional area 3mm2, 4mm2 and 5mm2 are made up of the same material and have the same lengths, which wire has the lowest resistance? a. 5mm2 area of cross section wire O b. 4mm2 area of cross section wire c. All three wires have the same О с. resistance O d. 3mm² area of cross section wire

University Physics Volume 2

18th Edition

ISBN:9781938168161

Author:OpenStax

Publisher:OpenStax

Chapter9: Current And Resistance

Section: Chapter Questions

Problem 71AP: A nichrome rod that is 3.00 mm long with a cross sectional area of 1.00 mm2 is used for a digital...

See similar textbooks

Similar questions

A metal wire of resistance R is cut into three equal pieces that are then placed together side by side to form a new cable with a length equal to one-third the original length. What is the resistance of this new cable? (a) 19R (b) 13R (c) R (d) 3R (e) 9R
In the circuit of Figure P18.22, the current I1 is 3.0 A and the values of and R are unknown. What are the currents I2 and I3? Figure P18.22
A nichrome rod that is 3.00 mm long with a cross sectional area of 1.00 mm2 is used for a digital thermometer, (a)What is the resistance at room temperature? (b)What is the resistance at body temperature?
Unreasonable Results (a) What current is needed to transmit 1.00 102 MW of power at 10.0kV? (b) Find the resistance of 1.00 km of wire that would cause a 0.0100% power loss. (c) What is the diameter of a 1.00-km-long copper wire having this resistance? (d) What is unreasonable about these results? (e) Which assumptions are unreasonable, or which premises are inconsistent?
Wire B has twice the length and twice the radius of wire A. Both wires are made from the same material. If wire A has a resistance R, what is the resistance of wire B? (a) 4R (b) 2R (c) R (d) 12R (e) 14R
(a) What is the resistance of a 1.00 102-O, a 2.50-k O, and a 4.00-kresistor connected in series? (b) In parallel?
A car battery with a 12-V emf and an internal resistance of 0.050 is being charged with a current of 60 A. Note that in this process the battery is being charged. (a) What is the potential difference across its terminals? (b) At what rate is thermal energy being dissipated in the battery? (c) At what rate is electric energy being converted to chemical energy? (d) What are the answers to (a) and (b) when the battery is used to supply 60 A to the starter motor?
Currents of approximately 0.06 A can be potentially fatal. Currents in that range can make the heart fibrillate (beat in an uncontrolled manner). The resistance of a dry human body can be approximately 100 k . (a) What voltage can cause 0.06 A through a dry human body? (b) When a human body is wet, the resistance can fall to 100 . What voltage can cause harm to a wet body?
The human body can exhibit a wide range of resistances to current depending on the path of the current, contact area, and sweatiness of the skin. Suppose the resistance across the chest from the left hand to the right hand is 1.0 106 . (a) How much voltage is required to cause possible heart fibrillation in a man, which corresponds to 500 mA of direct current? (b) Why should rubber-soled shoes and rubber gloves be worn when working around electricity?
A 20.00-V battery is used to supply current to a 10-k resistor. Assume the voltage drop across any wires used for connections is negligible, (a) What is the current through the resistor? (b) What is the power dissipated by the resistor? (c) What is the power input from the battery; assuming all the electrical power is dissipated by the resistor? (d) What happens to the energy dissipated by the resistor?
Consider the circuit shown in Figure P28.21 on page 860. (a) Find the voltage across the 3.00-0 resistor, (b) Find the current in the 3.00-12 resistor.
(a) Can the circuit shown in Figure P18.29 be reduced to a single resistor connected to the batteries? Explain. (b) Find the magnitude of the current and its direction in each resistor. Figure P18.29