Advertisements
Advertisements
प्रश्न
A wire of resistance 3 ohm and length 10 cm is stretched to length 30 cm. Assuming that it has a uniform cross section, what will be its new resistance?
Advertisements
उत्तर
Because three times the original length of the wire 10 cm is stretched to 30 cm
∴ Resistance becomes 9 times its resistance, i.e. 3 × 9 = 27 Ω
`"R"_1 = ρ 30/(a/3)`
= `9 [ρ 10/a]` ...(i)
`"R"_2 = ρ 10/a` put in (i)
R1 = 9R
= 9 × 3
= 27 Ω
∴ R = 3 Ω
APPEARS IN
संबंधित प्रश्न
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.
What is an Ohmic resistor?
Name the law which is illustrated by the above V−I graph.
In the circuit shown below in Fig, calculate the value of x if the equivalent resistance between A and B is 4 Ω.
What is meant by the drift speed of free electrons?
A wire connected to a power supply of 230 V has power dissipation P1. Suppose the wire is cut into two equal pieces and connected parallel to the same power supply. In this case, power dissipation is P2. The ratio of `"P"_2/"P"_1` is
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.
Which of the following is correct for V-I graph of a good conductor?
A heater of 220 V heats a volume of water m 5 mint time. A heater of 110 V heat in ten second. The resistance of the conductor is
