Power = (work done) / (time to do the work)
Work = (force) x (distance)
If you want to lift a 490N object, you'll need (at least) 490N of force.
So, when you lift it 2 meters vertically, the work you do is
Work = (490 N) x (2 m) = 980 joules
and
Power = (980 joules) / (10 sec) = 98 watts .
