Table of Contents
What is the resistance of a 25 watt bulb?
So the power is the voltage squared divided by its resistance and we can solve this for R by multiplying both sides by R over P and so resistance then is the voltage squared divided by the power. So that’s 120 volts squared divided by 25 watts, which is 580 ohms to two significant figures.
How do you find resistance when given power and voltage?
For example if the power is 100 watts and the voltage is 50 volts, the current is 100 / 50, or 2 amps. Calculate the resistance, in Ohms, by dividing the voltage by the current. Ohms law states that voltage = current x resistance, so by rearranging the formula resistance = voltage / current.
How do you calculate resistance in Watts?
Watts, Volts, Amps & Ohms Calculator
- Watt calculation/conversion formulas: watts = volts² / ohms. watts = amps² * ohms.
- Volt calculation/conversion formulas: volts = √ watts * ohms. volts = watts / amps.
- Amp calculation/conversion formulas: amps = volts / ohms.
- Ohms calculation/conversion formulas: ohms = volts / amps.
How many W is 230v?
Actually, 230v is equal to 450watts.
How do you find 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.
What is the relation of power and resistance?
The power dissipated in a resistor is given by P = V2/R which means power decreases if resistance increases. Yet this power is also given by P = I2R, which means power increases if resistance increases.
How many volts is 30 watts?
Equivalent watts and volts for various current ratings
| Power | Voltage | Current |
|---|---|---|
| 30 Watts | 15 Volts | 2 Amps |
| 30 Watts | 10 Volts | 3 Amps |
| 30 Watts | 7.5 Volts | 4 Amps |
| 35 Watts | 35 Volts | 1 Amps |
How do you calculate voltage drop resistance?
You know the resistance and the current (which is the same anywhere in a series circuit). The voltage drop for each resistor is E(x) = I x R(x) for each resistor (x), i.e., R(1), R(2), R(3).