Scooting Through Deep Water

Will it take more energy (battery power) to move a underwater scooter at 10ft than at 100ft? You would have more pressure on the scooter at 100ft but the density of the water would be the same.
- Mark
Denver, CO USA

I can't answer the question definitely for a particular scooter, which might be optimized for some particular conditions. Generally, however, the power required to travel at some chosen speed will increase as the viscosity (the property that affects the friction) of the water increases. It turns out that for water that's not particularly warm (<33°C) the viscosity goes down as the pressure increases (), with the range of pressures you care about. So in principle less energy is needed to scoot about at the deeper level.

Mike W.

Another reference, http://wiki.xtronics.com/index.php/Viscosity shows only slight dependence on pressure.

LeeH

(published on 10/24/2010)