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## Main Question or Discussion Point

Take for example an electric helicopter - to keep it suspended motionless in the air takes a force from the propeller(s) equal to the force of mass times gravity.

I would like to know the energy required per unit of time to keep this helicopter in the air, assuming 100% efficiency.

I'm not sure if this is even possible - I know that a watt is 1 joule per second, and that a joule is the force required to move 1kg 1 meter. However, since my object is at rest the equation W=FD states that there is no work done - and that there is no power (watts) required to keep it in the air.

However something has to counteract the force of gravity, my question is - is there a way to calculate the energy required to exert that force?

Thanks guys, this is just a theoretical question I was thinking about earlier.. my first post here too :D

I would like to know the energy required per unit of time to keep this helicopter in the air, assuming 100% efficiency.

I'm not sure if this is even possible - I know that a watt is 1 joule per second, and that a joule is the force required to move 1kg 1 meter. However, since my object is at rest the equation W=FD states that there is no work done - and that there is no power (watts) required to keep it in the air.

However something has to counteract the force of gravity, my question is - is there a way to calculate the energy required to exert that force?

Thanks guys, this is just a theoretical question I was thinking about earlier.. my first post here too :D