The total resistance in parallel is calculated using the formula: 1/Rt = 1/R1 + 1/R2 + 1/R3 + ... where Rt is the total resistance and R1, R2, R3, etc. are the individual resistances. In this case, we would have 1/Rt = 1/3 + 1/12, which simplifies to 1/Rt = 4/12, or Rt = 3 ohms.
The purpose of using different resistors in parallel is to achieve a specific desired resistance. By using a combination of 3 and 12 ohm resistors, we can create a total resistance of 2.4 ohms, which may be needed for a particular circuit or application.
Yes, as long as you understand the relationship between resistors in parallel and how to calculate the total resistance. You can use any combination of resistors to achieve a desired resistance, as long as you follow the appropriate formula and take into account the value of each resistor.
The total resistance decreases as you add more resistors in parallel. This is because the more paths there are for the current to flow through, the easier it is for the current to pass through the circuit, resulting in a lower overall resistance.
Yes, resistors can also be connected in series to achieve a specific resistance. In this case, the total resistance is simply the sum of all the individual resistances. However, using resistors in parallel may be more efficient in some cases, as it allows for a lower overall resistance with fewer components.