In the context of a microwave oven, "1 1/2" typically refers to a cooking time setting. It means setting the microwave to cook or heat the food for one and a half minutes.
For most microwave ovens, you can enter the cooking time using a numeric keypad. So, to set the microwave to cook for 1 minute and 30 seconds (1 1/2 minutes), you would enter "1:30" or "1.5" and start the microwave. The microwave will then operate for one minute and thirty seconds before automatically stopping.
Always be attentive when using a microwave to avoid overcooking or overheating the food. Different microwave models may have slight variations in their settings, so it's a good idea to consult your microwave's user manual for specific instructions and safety guidelines.