A 2 Ω resistor and a 12 Ω resistor are connected in parallel. What is the total resistance?
Answer and explanation
Correct answer: A. 12/7 Ω
- Step 1: For parallel resistors .
- Step 2: , so Ω.
Answer
12/7 Ω.
Why not the others: 14 Ω: that is the formula for resistors in series. 7 Ω: it averages the two resistances. 24 Ω: it multiplies the resistances without dividing by their sum.
Practise more Electricity and Magnetism.
Free questions with an explanation for every one, and full timed General Secondary Certificate (Tawjihiya Kuwait) mock tests.
More Electricity and Magnetism questions
- Resistors of 2 Ω, 12 Ω and 6 Ω are connected in series. What is the total resistance?
- Resistors of 2 Ω, 6 Ω and 4 Ω are connected in series. What is the total resistance?
- Resistors of 3 Ω, 3 Ω and 6 Ω are connected in series. What is the total resistance?
- An appliance connected to a 110 V supply draws a current of 10 A. What is its power?
- A 1000 W heater is used for 6 hours. The electricity tariff is HK\$1.5 per kWh. What is the cost of using the heater?
- An ideal transformer has 500 turns in the primary coil and 25 turns in the secondary coil. The primary voltage is 240 V. What is the seconda…