Suppose we have a fan/blower that is working at sea level. It has a certain RPM against a specific voltage and current. We all know that. Now, that fan/blower has been brought to the top of a mountain where air is sufficiently less dense and the same voltage and current has been applied to the fan/blower. What will happen? Whether the RPM will increase or it will remain the same? Common sense tells that RPM will increase as the air that it has to blow is less dense. And higher RPM means the speed of air is faster in comparison to the sea level. Whatsoever, it's my thought and I want to check it.