What is the resistance of a tungsten light bulb?
Table of Contents
- 1 What is the resistance of a tungsten light bulb?
- 2 What is the resistance of a 40 W 120 V bulb when it is lighted?
- 3 How do you find the resistance of a tungsten wire?
- 4 Does tungsten have low resistance?
- 5 How do you calculate the resistance of a 40 watt bulb?
- 6 What is the resistance of 100 watt bulb?
What is the resistance of a tungsten light bulb?
Temperature coefficient of resistance for tungsten The typical cold resistance of a 100 W incandescent lamp is about 9.5 ohms.
What is the resistance of tungsten wire?
Resistivity and Temperature Coefficient at 20 C
| Material | Resistivity ρ (ohm m) | Temperature coefficient α per degree C |
|---|---|---|
| Copper | 1.68 | .00386 |
| Copper, annealed | 1.72 | .00393 |
| Aluminum | 2.65 | .00429 |
| Tungsten | 5.6 | .0045 |
What is the resistance of a 40 W 120 V bulb when it is lighted?
360 ohms
Since power, P, equals iV, P/V = i, so at 120 V, a 40-watt bulb draws 1/3 A. (The units in iV are (C/s)(N-m/C), or J/s, which are watts.) For a given resistance, V = iR, so the bulb’s resistance (when it has 120 volts across it) is 120/(1/3), or 360 ohms.
What is the resistance of a 60 watt light bulb?
240 Ω
In fact, the 120-Watt bulb would have a current of 1 Amp and a resistance of 120 Ω; the 60-Watt bulb would have a current of 0.5 Amp and a resistance of 240 Ω.
How do you find the resistance of a tungsten wire?
How do I calculate the resistance of a wire?
- Find out the resistivity of the material the wire is made of at the desired temperature.
- Determine the length and cross-sectional area of the wire.
- Divide the length of the wire by its cross-sectional area.
- Multiply the result from step 3 with the resistivity of the material.
What is relation between resistance of tungsten and the amount of heat produced by the bulb?
Answer: resistance of tungsten is high and resistance is directly proportional to heat.
Does tungsten have low resistance?
Tungsten is a good conductor. Resistivity of tungsten is only about twice that of aluminum, and tungsten has lower resistance than iron, steel, platinum, lead.
What is the resistivity of tungsten at 0 degree?
133Ω
Resistance of tungsten wire at 150oC is 133Ω. Its resistance temperature coefficient is 0.
How do you calculate the resistance of a 40 watt bulb?
40 Watts will have more resistance than 60 watts, so 40 watts will draw less current and 60 watts will draw more current than 40 watts. If you apply Ohms Law, I =W /V, so 40 /220 =0. 18 amperes, and R =V /I so 220 /0. 18 =1222 ohms for a 40 watts bulb and 814 ohms for a 60 watts bulb.
What is the resistance of a 120 volt 100w bulb?
For example, a 100 watt light bulb operating on 120 volts AC will have 144 ohms of resistance and will draw 0.833 Amps. Enter 100 in the Watts field and 120 in the Voltage field and press Calculate to find the resistance and current.
What is the resistance of 100 watt bulb?
100 watts = I * 110 volts. 100 / 110 = 0.909 amps. 110 / 0.909 = ~ 121 ohms for the 100 watt bulb.
How do you calculate the resistance of a light bulb?
Since it involves the relationship of power voltage, current, and resistance, using the formula I=P/V with P and V known to find the current, and then using the formula R=P/I^2 to find the resistance will be the right steps to take.