Copper and silicon is cooled from $300\; K$ to $60\; K$, the specific resistance
AIPMT 2001, Easy
Download our app for free and get started
The specific resistance or resistivity, $\rho=\rho_0(1+\alpha T)$
where $\alpha=$ temperature coefficient of resistivity is positive for metals (copper) and is negative for semiconductor (silicon). Thus, when cooling, resistivity decreases in copper and increases in silicon.
Download our appand get started for free
Experience the future of education. Simply download our apps or reach out to us for more information. Let's shape the future of learning together!No signup needed.*
Similar Questions
- 1A capacitor of capacitance $5\,\mu F$ is connected to a source of constant $emf$ of $200\,V$ for a long time, then the switch was shifted to contact $2$ from contact $1$ . The total amount of heat generated in the $500\,\Omega $ resistance, thereafter isView Solution
- 2A storage battery is connected to a charger for charging with a voltage of $12.5\,\,Volts$. The internal resistance of the storage battery is $1\,\,\Omega$ . When the charging current is $0.5\,\,A$, the emf of the storage battery is: ............... $volts$View Solution
- 3In a meter bridge experiment $\mathrm{S}$ is a standard resistance. $\mathrm{R}$ is a resistance wire. It is found that balancing length is $l=25 \;\mathrm{cm} .$ If $\mathrm{R}$ is replaced by a wire of half length and half diameter that of $\mathrm{R}$ of same material, then the balancing distance $\left.l^{\prime} \text { (in } \mathrm{cm}\right)$ will now beView Solution
- 4A metal wire of resistance $3\,\Omega $ is elongated to make a uniform wire of double its previous length. The new wire is now bent and the ends joined to make a circle. If two points on this circle make an angle $60^o$ at the centre, the equivalent resistance between these two points will beView Solution
- 5In India electricity is supplied for domestic use at $220 \,V$. It is supplied at $110 \,V$ in USA. If the resistance of a $60 \,W$ bulb for use in India is $R$, the resistance of a $60 \,W$ bulb for use in USA will beView Solution
- 6In the adjoining circuit shown the potential difference between points $A$ and $B$ will beView Solution
- 7Consider four conducting materials copper, tungsten, mercury and aluminium with resistivity $\rho_{ C }, \rho_{ T }, \rho_{ M }$ and $\rho_{ A }$ espectively Then:View Solution
- 8A hot electric iron has a resistance of $80\,\Omega $ and is used on a $200\, V$ source. The electrical energy spent, if it is used for two hours, will be ........... $Wh$View Solution
- 9For the circuit shown in the figureView Solution
$(A)$ the current $I$ through the battery is $7.5 \mathrm{~mA}$
$(B)$ the potential difference across $R_{\mathrm{L}}$, is $18 \mathrm{~V}$
$(C)$ ratio of powers dissipated in $R_1$ and $R_2$ is $3$
$(D)$ if $R_1$ and $R_2$ are interchanged, magnitude of the power dissipated in $R_{\mathrm{L}}$ will decrease by a factor of $9$
- 10Four identical electrical lamps are labelled $1.5\,V$, $0.5\,A$ which describes the condition necessary for them to operate at normal brightness. A $12\,V$ battery of negligible internal resistance is connected to lamps as shown, thenView Solution
