To apply the superposition theorem, all components must be:

Superposition Theorem:

• The superposition theorem states that "in a linear circuit with several sources, the current and voltage for any element in the circuit is the sum of the currents and voltages produced by each source acting independently."
• The superposition theorem applies only when all the components of the circuit are linear, which is the case for resistors, capacitors, and inductors it is not applicable to networks containing nonlinear elements.
  Additional Information

​ Superposition Theorem:

• It is stated that in any linear, active, bilateral network having more than one source, the response across any element is the Algebraic sum of the response obtained from each source considered separately and all other sources are replaced by their internal resistance.
• The principle of the superposition theorem is based on Linearity.
• Voltage Source  →   short
• Current source   →  open
• Do not disturb the dependent source present in the network.
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  Step to solving Network by superposition theorem

• Step 1 – Take only one independent source of voltage or current and deactivate the other sources.
• Step 2 – If there is a voltage source then short circuit it and if there is a current source then just open-circuit it.
• Step 3 – Thus, by activating one source and deactivating the other source find the current in each branch of the network.
• Step 4 – Now to determine the net branch current utilizing the superposition theorem, add the currents obtained from each individual source for each branch.
• Step 5 – If the current obtained by each branch is in the same direction then add them and if it is in the opposite direction, subtract them to obtain the net current in each branch.