Advertisements
Advertisements
प्रश्न
The resistance of a nichrome wire at 0°C is 10Ω. If its temperature coefficient of resistivity of nichrome is 0.004/ °C, find its resistance of the wire at boiling point of water. Comment on the result.
Advertisements
उत्तर
Given data:
R0 = 10Ω
The boiling point of water T = 100°C
α = 0.004°C
RT = ?
Formula:
RT = R0 [l + αT)]
RT = 10 [1 + (0.004 × 100)]
= 10(1 + 0.4)
= 10 (1.4)
RT = 14Ω
As the temperature increase the resistance of the wire also increases.
APPEARS IN
संबंधित प्रश्न
Will current flow more easily through a thick wire or a thin wire of the same material, when connected to the same source? Why?
What is an Ohmic resistor?
State Ohm’s law and draw a neat labelled circuit diagram containing a battery, a key, a voltmeter, an ammeter, a rheostat and an unknown resistance to verify it.
Two metallic spheres A and B kept on insulating stands are in contact with each other. A positively charged rod P is brought near the sphere A as shown in the figure. The two spheres are separated from each other, and the rod P is removed. What will be the nature of charges on spheres A and B?
Consider the sacle of voltmeter shown in the diagram and answer the following questions :
(a) What is the least count of the voltmeter?
(b) What is the reading shown by the voltmeter ?
(c) If the voltmeter is connected across a resistor of 20 `Omega` how much current is flowing through the resistor?
What is non ohmic device?
Explain the equivalent resistance of a parallel resistor network.
A metal rod of length 10 cm and a rectangular cross-section of 1 cm × `1/2` cm is connected to a battery across opposite faces. The resistance will be ______.
Let the resistance of an electrical device remain constant, while the potential difference across its two ends decreases to one fourth of its initial value. What change will occur in the current through it? State the law which helps us in solving the above stated question.
A current of 3.2 mA flows through a conductor. If charge on an electron is −1.6 × 10-19 coulomb, find the number of electrons that will pass each second through the cross section of that conductor.
