A metallic resistor is connected across a battery. If the number of collisions of the free electrons with the lattice is somehow decreased in the resistor (for example, by cooling it), the current will:
1. increase
2. decrease
3. remain constant
4. become zero
Two resistors A and B have resistances RA and RB respectively with RA < RB . The resistivities of their materials are ρA and ρB
1. ρA > ρB
2. ρA = ρB
3. ρA < ρB
4. The information is not sufficient to find the relation between ρA and ρB
The product of resistivity and conductivity of a cylindrical conductor depends on
1. temperature
2. material
3. area of cross-section
4. none of these.
As the temperature of a metallic resistor is increased, the product of its resistivity and conductivity:
1. | increases |
2. | decreases |
3. | remains constant |
4. | may increase or decrease |
A uniform wire of resistance \(50~\Omega\) \(\) is cut into \(5\) equal parts. These parts are now connected in parallel. The equivalent resistance of the combination is:
1. \(2~\Omega\) \(\)
2. \(10~\Omega\) \(\)
3. \(250~\Omega\) \(\)
4. \(6250~\Omega\) \(\)
Which of the following quantities do not change when a resistor connected to a battery is heated due to the current?
a. | drift speed |
b. | resistivity |
c. | resistance |
d. | the number of free electrons |
Choose the correct option:
1. (d) only
2. (b), (c)
3. (c), (d)
4. (a), (d)