Welcome to the Quiz!
This quiz contains 16 questions from a mix of 1 subtopics.
What is the unit used to measure resistivity?
watt (W)
volt (V)
ohm-metre (Ωm)
ampere (A)
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If the length of a wire is doubled, what happens to its resistance?
it halves
it doubles
it stays the same
it quadruples
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Which of the following affects the resistance of a conductor?
length
all of the above
cross-sectional area
resistivity
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What is the equation linking resistivity, length, area and resistance?
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If the diameter of a wire is halved, what happens to its resistance?
it quadruples
it halves
it stays the same
it doubles
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What would happen if the cross-sectional area of a wire were increased?
the resistance would increase
the resistivity would decrease
the resistance would decrease
the resistivity would increase
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What term refers to materials that obey Ohm's law at steady temperatures?
non-ohmic conductors
superconductors
variable resistors
ohmic conductors
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If voltage applied across a wire is increased, what happens to the current through the wire?
it stays the same
it doubles
it increases
it decreases
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What does resistivity depend on? Select all that apply.
type of material
current
magnetic field strength
temperature
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What does the gradient of the length vs. resistance graph represent when determining resistivity experimentally?
resistivity x Area
resistivity/Area
area
length
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What device is used to measure the diameter of a wire?
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State three ways the resistance of a length of straight wire could be decreased.
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A 3-meter-long aluminium wire with a cross-sectional area of 1 x 10-6 m2 has a resistivity of 2.82 x 10-8 Ω m. Calculate the resistance of the wire.
0.085 Ω
0.094 Ω
0.093 Ω
0.152 Ω
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Calculate the resistance of a nichrome wire that is 4 metres long and 0.5 mm in diameter, given that the resistivity of nichrome is 1.1 x 10-6 Ω m.
2.85 Ω
7.34 Ω
14.83 Ω
22.45 Ω
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What is the resistance of a 5-meter-long silver wire with a diameter of 1 mm, knowing that the resistivity of silver is 1.59 x 10-8 Ω m?
0.10 Ω
0.03 Ω
0.18 Ω
0.25 Ω
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A student records a voltage of 6 V across a wire and a current of 2 A flowing through it. If the wire is 1.5 meters long and has a diameter of 0.02 m, calculate its resistivity.
1.54 x 10-4 Ω m
2.54 x 10-4 Ω m
6.28 x 10-4 Ω m
3.67 x 10-4 Ω m
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