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.
What is the resistance of electric bulb?
The typical cold resistance of a 100 W incandescent lamp is about 9.5 ohms. If that resistance stayed the same with 120 V applied, Ohm’s Law tells us that the bulb would draw about 12.5 amps and dissipate about 1,500 watts.
How do you calculate electric resistance?
R = V ÷ I Question
What is the resistance of the lamp? To calculate the resistance of an electrical component, an ammeter is used to measure the current and a voltmeter to measure the potential difference. The resistance can then be calculated using Ohm’s Law.
What is the resistance of a 200 watt light bulb?
So, the resistance is 312.5 ohms.
How can we calculate the exact current and resistance of 100 W bulb?
Also, Power can be calculated by P=I*E current in amps times voltage, for example, one amp and one hundred volts =100 watts. Resistance can be calculated by R= E/I , voltage divided by current in amps.
What is the resistance of a 12v bulb?
Each incandescent bulb (12-volt/system) measures 1.5 ohms with a meter; however, there is no resistance across the LED [replacement] bulbs.
How do you solve for resistance?
Ohms Law and Power
- To find the Voltage, ( V ) [ V = I x R ] V (volts) = I (amps) x R (Ω)
- To find the Current, ( I ) [ I = V ÷ R ] I (amps) = V (volts) ÷ R (Ω)
- To find the Resistance, ( R ) [ R = V ÷ I ] R (Ω) = V (volts) ÷ I (amps)
- To find the Power (P) [ P = V x I ] P (watts) = V (volts) x I (amps)
What is the equation for resistivity?
Resistivity, commonly symbolized by the Greek letter rho, ρ, is quantitatively equal to the resistance R of a specimen such as a wire, multiplied by its cross-sectional area A, and divided by its length l; ρ = RA/l. The unit of resistance is the ohm.
What is the resistance of a small light bulb?
(A typical bulb has a resistance of 7 to 8 ohms through the filament and 2 to 3 ohms through the shunt once the coating burns off.) Although you can buy simple 50-bulb strands like the one shown above, it is more common to see 100- or 150-bulb strands.
Why does a light bulb have resistance?
The filament of a light bulb is an extremely thin wire. This thin wire resists the flow of electrons.
Does higher resistance mean brighter bulb?
An incandescent bulb’s brightness depends on a whole lot on resistance. The higher the resistance to current in the wiring, circuitry, and bulb, the lower will be the current, lower the power, and lower the brightness. Conversely, lower resistance means more brightness.
Are bulbs brighter in series or parallel?
Two light bulbs on the same series circuit share the voltage of the battery: if the battery is 9V, then each bulb gets 4.5 volts. … Two bulbs in a simple parallel circuit each enjoy the full voltage of the battery. This is why the bulbs in the parallel circuit will be brighter than those in the series circuit.