Dependence of...

Dependence of Resistance on Temperature

Trending Questions

Two identical resistors, each of resistance $15 ohm$ , are connected in (i) series, and (ii) parallel, in turn to a battery of $6 V$ . Calculate the ratio of the power consumed in the combination of resistors in each case.

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Q. A nichrome element has a resistance of

75.3 Ω

27^{\circ} C

. When 230 V p.d is applied and a study state temperature is reached, the current flowing through it is 2.68 A. If

\propto= 1.7 \times 10^{- 4 \circ} C^{- 1}

, find the steady state temperature

$1000^{\circ} C$
$700^{\circ} C$
$950^{\circ} C$
$848^{\circ} C$

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Q. A conductor has a resistance

5 Ω

50^{\circ} C

and

6 Ω

100^{\circ} C

. Find its resistance at

0^{\circ} C

$4 Ω$
$3 Ω$
$2 Ω$
$1 Ω$

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Q. A loop (circuit) is placed in uniform magnetic field

\to B

and flux through the loop is given by

ϕ = 4 t

. Find the power supplied to the

6 V

battery.

$5 W$
$3 W$
$2 W$
$6 W$

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Q. The resistance of a wire at

20^{\circ} C

20 Ω

and at

500^{\circ} C

60 Ω

. At which temperature resistance will be

25 Ω

$50^{\circ} C$
$60^{\circ} C$
$70^{\circ} C$
$80^{\circ} C$

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Q. Two wires of resistance

R_{1}

and

R_{2}

have temperature co-efficient of resistance

α_{1}

and

α_{2}

respectively. These are joined in series. The effective temperature co-efficient of resistance is

$\frac{α_{1} + α_{2}}{2}$
$\sqrt{α_{1}} α_{2}$
$\frac{α_{1} R_{1} + α_{2} R_{2}}{R_{1} + R_{2}}$
$\frac{\sqrt{R_{1} R_{2} α_{1} α_{2}}}{\sqrt{R_{1}^{2} + R_{2}^{2}}}$

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Q. The temperature coefficient of resistance for a wire is

{0.00125}^{\circ} C^{- 1}

. At 300 K, its resistance is

1 Ω

. The temperature at which the resistance becomes

1.5 Ω

450 K
713 K
454 K
900 K

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Q. The current voltage (I – V) graphs for a given metallic wire at two different temperatures

T_{1}

and

T_{2}

are shown in figure. If follows from the graphs that

$T_{1} > T_{2}$
$T_{1} < T_{2}$
$T_{1} = T_{2}$
$T_{1}$ is greater or less than $T_{2}$ depending on whether the resistance R of the wire is greater or less than the ratio $V / I$

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Q. With increase in temperature, the resistivity of a semiconductor?

Increases
Decreases
Remains constant
Becomes zero

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Q. The operating temperature of the filament of lamp is

2000^{\circ} C

. The temperature coefficient of the material of filament is

0.005^{\circ} C^{- 1}

. If the atmospheric temperature is

0^{\circ} C

, then the current in the

100 W - 200 V

lamp when it is switched on is nearest to

$2.5 A$
$3.5 A$
$4.5 A$
$5.5 A$

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Q. A metallic resistor is connected across a battery. If the number of collisions of the free electrons with the lattice is decreased in the resistor by cooling it, the current will?

Increase
Decrease
Remains constant
Becomes zero

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Q. A brass disc and a carbon disc of same radius are assembled alternatively to make a cylindrical conductor. The resistance of the cylinder is independent of the temperature. The ratio of thickness of the brass disc to that of the carbon disc is
[

α_{B}

and

α_{C}

are respectively the temperature coefficients of resistance of brass and carbon &

ρ_{B}

and

ρ_{C}

are respectively the resistivities of brass and carbon. Neglect linear expansion]

$∣ ∣ ∣ \frac{α_{C} ρ_{C}}{α_{B} ρ_{B}} ∣ ∣ ∣$
$∣ ∣ ∣ \frac{α_{C} ρ_{B}}{α_{B} ρ_{C}} ∣ ∣ ∣$
$∣ ∣ ∣ \frac{α_{B} ρ_{C}}{α_{C} ρ_{B}} ∣ ∣ ∣$
$∣ ∣ ∣ \frac{α_{B} ρ_{B}}{α_{C} ρ_{C}} ∣ ∣ ∣$

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Q. The temperature coefficient of resistance for a wire is 0.00125

/^{\circ} C

. At 300K its resistance is 1 ohm. The temperature at which the resistance becomes 2 ohm is

1154 K
1100 K
1400 K
1127 K

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Q. The temperature coefficient of resistance of a conductor varies as

α (T) = 3 T^{2} + 2 T

. If

R_{0}

is resistance at

T = 0

and

R

be resistance at

T

then

$R = R_{0} (6 T + 2)$
$R = 2 R_{0} (3 + 2 T)$
$R = R_{0} (1 + T^{2} + T^{3})$
$R = R_{0} (1 - T + T^{2} + T^{3})$

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Q. The temperature co-efficient of resistance of a wire is

0.00125 /^{\circ} C

. At 300 K , it’s resistance is

1 Ω

. The resistance of the wire will be

2 Ω

1154 K
1127 K
600 K
1400 K

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Q. The temperature coefficient of resistance for a wire is

{0.00125}^{\circ} C^{- 1}

. At 300 K, its resistance is

1 Ω

. The temperature at which the resistance becomes

1.5 Ω

450 K
713 K
454 K
900 K

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Q. The current voltage (I – V) graphs for a given metallic wire at two different temperatures

T_{1}

and

T_{2}

are shown in figure. If follows from the graphs that

$T_{1} > T_{2}$
$T_{1} < T_{2}$
$T_{1} = T_{2}$
$T_{1}$ is greater or less than $T_{2}$ depending on whether the resistance R of the wire is greater or less than the ratio $V / I$

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Q. A conductor has a reistance R, at

t_{1}^{0} C

and R2 at

t_{2}^{0} C

. Find

\propto (i n^{\circ} C^{- 1})

$\frac{R_{2} - R_{1}}{R_{1} t_{1} - R_{2} t_{2}}$
$\frac{R_{2} - R_{1}}{R_{1} t_{2} - R_{2} t_{1}}$
$\frac{R_{2} + R_{1}}{R_{1} t_{1} + R_{2} t_{2}}$
$\frac{R_{2} + R_{1}}{R_{1} t_{2} + R_{2} t_{1}}$

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Q. A conductor has a reistance R, at

t_{1}^{0} C

and R2 at

t_{2}^{0} C

. Find

\propto (i n^{\circ} C^{- 1})

$\frac{R_{2} - R_{1}}{R_{1} t_{1} - R_{2} t_{2}}$
$\frac{R_{2} - R_{1}}{R_{1} t_{2} - R_{2} t_{1}}$
$\frac{R_{2} + R_{1}}{R_{1} t_{1} + R_{2} t_{2}}$
$\frac{R_{2} + R_{1}}{R_{1} t_{2} + R_{2} t_{1}}$

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Q. The temperature co-efficient of resistance of a wire is

0.00125 /^{\circ} C

. At 300 K , it’s resistance is

1 Ω

. The resistance of the wire will be

2 Ω

1154 K
1127 K
600 K
1400 K

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Q. Two resistor A and B have resistances

R_{A} a n d R_{B}

respectively with

R_{A} < R_{B}

. The resistivity of their materials are

ρ_{A} a n d ρ_{B}

$ρ_{A} > ρ_{B}$
$ρ_{A} = ρ_{B}$
$ρ_{A} < ρ_{B}$
$D a t a i n s u f f c i e n t$

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