Advertisements
Advertisements
Question
Fill in the following blank with suitable words:
Resistance is measured in .............. The resistance of a wire increases as the length ..............; as the temperature ..............; and as the cross-sectional area .............. .
Solution
Resistance is measured in ohm (Ω). The resistance of a wire increases as the length increases; as the temperature increases; and as the cross-sectional area decreases.
APPEARS IN
RELATED QUESTIONS
What will be the change in the current if the potential difference is kept constant and the resistance of the circuit is made four times?
- It will remain unchanged.
- It will become four times.
- It will become one-fourth.
- It will become half.
Why are coils of electric toasters and electric irons made of an alloy rather than a pure metal?
When a 12 V battery is connected across an unknown resistor, there is a current of 2.5 mA in the circuit. Find the value of the resistance of the resistor.
A low voltage supply from which one needs high currents must have very low internal resistance. Why?
Name the unit of electrical resistance and give its symbol.
How would you connect two resistors in series? Draw a diagram. Calculate the total equivalent resistance.
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?
State and define Ohm’s law.
The resistance of a resistor is reduced to half of its initial value. If other parameters of the electrical circuit remain unaltered, the amount of heat produced in the resistor will become ______.
