Not necessarily. Microwaving two things at the same time can affect the cooking time, but it doesn't always mean you need to double it. The cooking time will depend on several factors:
Power settings: If you microwave two items together, the power may be distributed between them, which could result in slightly longer cooking times for both compared to when microwaving them separately at full power.
Food quantity and arrangement: If the items are placed densely together, they might shield each other from the microwave energy, causing uneven cooking. You might need to rearrange them midway through cooking to ensure even results.
Food type and density: Different foods have different cooking times and densities. If the two items you're microwaving have vastly different cooking times, you may need to remove one before the other is fully cooked.
Microwave wattage: The wattage of your microwave also plays a significant role in cooking times. If you're using a lower wattage microwave, cooking times may be longer compared to higher wattage microwaves.
For certain items that have similar cooking times and can be arranged properly in the microwave, you can start with the recommended cooking time for a single item and then check their doneness periodically. Adjust the cooking time as needed based on their progress.
It's important to use caution when microwaving multiple items together to avoid undercooking or overcooking. When in doubt, it's safer to cook items separately to ensure each one is cooked thoroughly and evenly.