Kennebecasis Rowing Club
Physics of Rowing
Things that make you say ahhhhhhhhhhhhh.
Also includes formulas for those physic enthusiast.
FAQ: Physics of Rowing Prepared by Dr. A. Dudhia (dudhia@atm.ox.ac.uk) Dept. Atmospheric Physics, Oxford University, an ARA Silver Level coach and surprisingly slow sculler from St Catherine's College BCRecent modifications: 29-AUG-04 Comments/corrections from Hans Lohse. None of the following information is copyright, so feel free to reproduce any or all of it, credited or uncredited as you see fit (although I might be a bit miffed if anyone else tried to pass it off as their own work). Contents of this page FAQ: Basic Physics of Rowing FAQ: Physics of Weight & Rowing FAQ: Physics of Stream/Depth & Rowing FAQ: Physics of Ergometers Bibliography & References Credits Rowing FAQ (Hannes Hofer) covers a lot of the terminology used here FAQ: Basic Physics of Rowing Propulsion Why does the blade have to slip in the water? (when it doesn't if you push off a solid object?) Resistance What causes a boat to slow down? Why don't you go twice as fast if you pull twice as hard? Kinetic Energy Why are 'cleavers' a good idea ? (when you can get the same impulse from smaller blades?) Centre of Mass Why do boats continue to accelerate (and move quickest) after the end of the stroke? Speed Variation Why is it more efficient to row a piece with constant split-times? Why is it more efficient to keep the hull speed as uniform as possible during the stroke? Why were `sliding rigger' boats banned? Balance Why do/don't boats balance? Why is it easier to balance a moving boat? Levers What type of lever is an oar? Why does the boat move forwards although I'm pushing it backwards with my feet? Gearing What is meant by the gearing of an oar? Why is gearing expressed in terms of the span (or spread) rather than the inboard? Why is changing the span 1cm supposed to be 3 times as effective as moving the button the same distance? What are CLAMS and why are they used? Why are cleavers shorter than the equivalent Macon oars? Newton's Laws of Motion FAQ: Physics of Weight & Rowing Introduction How do erg scores/boat speed depend on bodyweight? Relationship between Power and Weight Why and how do Aerobic and Anaerobic power depend on weight? Power/Weight Ratios How do Power/Weight ratios depend on weight? Relationship between Weight and Erg Speed Why do heavier rowers have an advantage on Erg scores Where does the 2/9 (or 0.222) exponent in erg-conversion scores come from? Relationship between Weight and Boat Speed Why are heavier rowers faster than lighter rowers? Why is this difference less obvious over long distances? Speeds of different Boat Classes Why are boats with more rowers faster? How much faster are they? How fast should an octuple scull be? Effect of deadweight What is the effect of deadweight on boat speed? How much does the weight of the cox affect the boat speed? Relationship between Erg Score and Boat Speed How do you convert erg-scores of rowers of different weights into equivalent boat speed? If I lose weight, how much faster would I scull? If I lose weight, how much should my erg score be allowed to drop in order to maintain the same boat speed? Effect of Boat Weight on Boat Speed Is a "lighter" boat necessarily a "faster" boat? FAQ: Physics of Stream/Depth & Rowing Introduction Which feels `heavier': rowing upstream or downstream? Viscosity What is viscosity? Why is viscous drag said to be proportional to velocity? Boat Resistance Why does boat resistance vary as velocity-squared? (when viscous drag is usually said to be proportional to velocity) River Flow Why does a river flow quickest where it is deepest? Upstream/Downstream Resistance Why does rowing upstream feel `lighter' than rowing downstream? Shallow Water Resistance Why does rowing in shallow water feel heavier than deep water? How shallow does water have to be before you notice? Upstream/Downstream times Why is the average time for upstream + downstream pieces slower when the stream is faster? (when you'd expect the stream effect to cancel) FAQ: Physics of Ergometers Introduction What are the different types of Ergometers? Where can I find more information about each type of Ergometer? Mechanics of Rotating Bodies How do Newton's Laws apply to rotating bodies ? Power Dissipation Why/how do ergometers lose speed ? Power Supplied How does power supplied turn into rotation speed? How does power relate to the flywheel speed ? Changing the Cog What is the effect of changing the cog (sprocket) size? Changing the Damping What is the effect of changing the damper setting ? Measuring the Damping How does the ergometer `know' what damper setting is used ? What other effects are/are not allowed for by the ergometer ? Measuring the Power Supplied How does the ergometer calculate the indicated `Power' ? Indicated Speed (Splits) and Distance How does the ergometer calculated the speed and distance ? Indicated Power v. Indicated Speed (Splits) What is the relationship between indicated Power and Speed? Power v. Indicated Calories What is the "Calories" output on the monitor ? What is the relationship between indicated Power and Calories? Dynamic v. Static Ergs What is the difference between moving and stationary ergs? Why are `dynamic' ergs better boat simulators Why do you get higher scores using the Concept `slide' Effect of Rating How does rating affect the power required ? Why do people erg at lower rates than they row/scull? Effect of Altitude What is the effect of altitude on erg scores? Glossary of terms used in Rotational Mechanics What are the various terms used in studying rotational systems?
