Introduction to Volts Current and Resistance

Copper is a metal commonly used for electrical wiring in houses. Which metal conducts electricity better than copper at 20^oC?

• nichrome

• gold

• silver

• aluminum

The diagrams above represent four pieces of copper wire at 20.^oC. For each piece of wire, L represents a unit of length and A represents a unit of cross-sectional area.

The piece of wire that has the greatest resistance is

• wire 1

• wire 2

• wire 3

• wire 4

An MP3 player draws a current of 0.120 ampere from a 3.00-volt battery. What is the total charge that passes through the player in 900. seconds?

• 324 C

• 108 C

• 1.80 C

• 5.40 C

What is the current in a wire if 3.4 x 10¹⁹ electrons pass by a point in this wire every 60. seconds?

• 11 A

• 3.1 x 10^-11 A

• 9.1 x 10^-2 A

• 1.8 x 10^-18 A

Tags

NGSS.HS-PS2-5

What is the resistance of a 20.0-meter long tungsten rod with cross-sectional area of 1.00 x 10^-4 meters² at 20^oC?

• 112 ohms

• 1.12 x 10^-2 ohms

• 89.3 ohms

• 2.80 x 10^-5 ohms

The resistance of a circuit remains constant. Which graph best represents the relationship between the current in the circuit and the potential difference provided by the battery?

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Resistivity, the inverse of conductivity, is dependent on which of the following? (choose one)

• shape of the wire

• length of the wire

• cross-sectional area of the wire

• type of metal

The resistance of a material

• depends on its resistivity and the geometric properties of the material.

• does not depend on its resistivity or the geometric properties of the material.

• depends on its resistivity but not the geometric properties of the material.

• does not depend on its resistivity but on the geometric properties of the material.

Wire A has twice the cross sectional area of wire B. The resistance of wire B is __________________ wire A.

• 1/4 as much as

• 1/2 as much as

• the same as

• twice as much as

How will increasing the amount of resistance in a circuit affect the current if the voltage remains constant?

• It will increase

• It will not change

• It will decrease

• It will cease