(i) Resistivity of iron = 10.0 x 10-8 Ω m Resistivity of mercury = 94.0 x 10-8 Ω m. Thus iron is a better conductor because it has lower resistivity than mercury. (ii) Because silver has the lowest resistivity (= 1.60 x 10-8 Ω m), therefore silver is the best conductor.
(i) Resistivity of iron = 10.0 x 10-8 Ω m
Resistivity of mercury = 94.0 x 10-8 Ω m.
Thus iron is a better conductor because it has lower resistivity than mercury.
(ii) Because silver has the lowest resistivity (= 1.60 x 10-8 Ω m), therefore silver is the best conductor.
The coils of electric toasters, electric irons and other heating devices are made of an alloy rather than a pure metal because (i) the resistivity of an alloy is much higher than that of a pure metal, and (ii) an alloy does not undergo oxidation (or burn) easily even at high temperature, when it isRead more
The coils of electric toasters, electric irons and other heating devices are made of an alloy rather than a pure metal because
(i) the resistivity of an alloy is much higher than that of a pure metal, and
(ii) an alloy does not undergo oxidation (or burn) easily even at high temperature, when it is red hot.
When potential difference is halved, the current through the component also decreases to half of its initial value. This is according to ohm’s law i.e., V ∝ I.
When potential difference is halved, the current through the component also decreases to half of its initial value. This is according to ohm’s law i.e., V ∝ I.
The current will flow more easily through a thick wire than a thin wire of the same material. Larger the area of cross-section of a conductor, more is the ease with which the electrons can move through the conductor. Therefore, smaller is the resistance of the conductor.
The current will flow more easily through a thick wire than a thin wire of the same material. Larger the area of cross-section of a conductor, more is the ease with which the electrons can move through the conductor. Therefore, smaller is the resistance of the conductor.
Use the data in Table 12.2 to answer the following –
(i) Resistivity of iron = 10.0 x 10-8 Ω m Resistivity of mercury = 94.0 x 10-8 Ω m. Thus iron is a better conductor because it has lower resistivity than mercury. (ii) Because silver has the lowest resistivity (= 1.60 x 10-8 Ω m), therefore silver is the best conductor.
(i) Resistivity of iron = 10.0 x 10-8 Ω m
See lessResistivity of mercury = 94.0 x 10-8 Ω m.
Thus iron is a better conductor because it has lower resistivity than mercury.
(ii) Because silver has the lowest resistivity (= 1.60 x 10-8 Ω m), therefore silver is the best conductor.
Why are coils of electric toasters and electric irons made of an alloy rather than a pure metal?
The coils of electric toasters, electric irons and other heating devices are made of an alloy rather than a pure metal because (i) the resistivity of an alloy is much higher than that of a pure metal, and (ii) an alloy does not undergo oxidation (or burn) easily even at high temperature, when it isRead more
The coils of electric toasters, electric irons and other heating devices are made of an alloy rather than a pure metal because
(i) the resistivity of an alloy is much higher than that of a pure metal, and
(ii) an alloy does not undergo oxidation (or burn) easily even at high temperature, when it is red hot.
See lessLet the resistance of an electrical component remains constant while the potential difference across the two ends of the component decreases to half of its former value. What change will occur in the current through it?
When potential difference is halved, the current through the component also decreases to half of its initial value. This is according to ohm’s law i.e., V ∝ I.
When potential difference is halved, the current through the component also decreases to half of its initial value. This is according to ohm’s law i.e., V ∝ I.
See lessWill current flow more easily through a thick wire or a thin wire of the same material, when connected to the same source? Why?
The current will flow more easily through a thick wire than a thin wire of the same material. Larger the area of cross-section of a conductor, more is the ease with which the electrons can move through the conductor. Therefore, smaller is the resistance of the conductor.
The current will flow more easily through a thick wire than a thin wire of the same material. Larger the area of cross-section of a conductor, more is the ease with which the electrons can move through the conductor. Therefore, smaller is the resistance of the conductor.
See lessOn what factors does the resistance of a conductor depend?
The resistance of a conductor depends (i) on its length (ii) on its area of cross-section and (iii) on the nature of its material.
The resistance of a conductor depends
(i) on its length
(ii) on its area of cross-section and
(iii) on the nature of its material.
See less