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Electric circuitsPhysicsHigh schoolabout 0:53

Resistors of 100, 220 Ω are connected in series to a 9 V battery. Find the total resistance and current: animated lesson

A narrated, step-by-step electric circuits video lesson with captions. Final answer: R_T = 320 Ω; I = 0.028125 A, P = 0.253125 W.

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Video with a synthetic English voice and captions. Pick another language for subtitles in that language, or open the interactive version.

Video narrated by a synthetic voice (Piper TTS, en_US-ljspeech-high voice (LJ Speech dataset, public domain)); the steps come from our maths engine and the answer was checked independently. Download MP4 (0.4 MB) · Captions (WebVTT)

Steps on screen

1. The problem
Worked example
Resistors of 100, 220 Ω are connected in series to a 9 V battery. Find the total resistance and current.
2. Step by step
1. $R_T = 100 + 220 = 320\ \Omega$
  Series: resistances add
2. $I = \frac{V}{R_T} = \frac{9}{320} = 0.028125\ \text{A}$
  Total current from Ohm's law
3. $V_{1} = 2.8125\ \text{V},\ V_{2} = 6.1875\ \text{V}$
  Voltage across each resistor (same current)
4. $P = VI = 0.253125\ \text{W}$
  Power delivered
3. The answer
$\text{R\_T = 320 Ω; I = 0.028125 A, P = 0.253125 W}$
R_T = 320 Ω; I = 0.028125 A, P = 0.253125 W
4. Check
- R_T ≥ every individual resistor ✓

Transcript

The problem. Here is the problem: Resistors of 100, 220 Ω are connected in series to a 9 V battery. Find the total resistance and current. Resistors in series carry the same current; their resistances add.

Step by step. Series: resistances add. Total current from Ohm prime s law. Voltage across each resistor (same current). The drops add up to the supply voltage. Power delivered.

The answer. So the answer is R T equals 320 Ω; I equals 0.028125 A, P equals 0.253125 W. The equivalent resistance of a series chain is always larger than its largest resistor.

Check. R T greater than or equal to every individual resistor, which checks out.

About electric circuits

Ohm's law, electrical power and resistors in series and parallel.

Resistors of 100, 220 Ω are connected in series to a 9 V…