Physics of Sailing

Physics of Sailing

Length: 1099 words (3.1 double-spaced pages)

Rating: Excellent

Open Document

Essay Preview

More ↓
A boat floating can be greatly appreciated, especially if you are in the boat at the time. But what keeps a boat from sinking? Physics can explain these concepts. There are many forces that act on a sailing ship to put it in motion, but the buoyant force is what is required to keep the boat from sinking. A buoyant force is the normal force that pushes up on the boat supporting its weight in a fluid. The buoyant force "equals the weight of the fluid displaced by the object."(pg.427, Serway and Jewett) This concept is Archimede's Principle.

The pressure on an object in a fluid varies with the depth of that part of the object in the fluid.

B=(P b – P t)A = (ρ fluidgh)A = ρ fluidgV

B=Buoyant force

P b=pressure at bottom

P t=pressure at top

A=area of bottom face

ρ fluid=fluid density


h= height

V=volume of fluid displaced by object

(formula from pg. 428, Serway and Jewett)

"The fraction of the volume of a floating object that is below the fluid surface is equal to the ratio of the density of the object to that of the fluid."(p.429, Serway and Jewett)

V fluid/Vobj = ρ obj/ρ fluid

Vobj=volume of the object

ρ obj=density of the object

Buoyancy of the craft is created by the shape of the hull, but also with buoyant materials in specific places. Air tanks, buoyancy bags, and polystyrene blocks are all used to add buoyancy to a boat.

The figure below shows how the buoyant material should be distributed and the effects if it is not.
figure from The Handbook of Sailing

The distrubution of buoyancy is key to having the boat float properly.

Bernoulli's principle is that the air moving past a foil, an object that has one curved side and one flat side, will take longer to move past the curved side than the flat side of the foil. This will cause the flat side to have higher air pressure and to exert a force on the object. The force cause a planes wing to lift and a sail to push a boat. "With the wind pushing on one side of the sails and the water pushing on the other side of the centerboard, the boat moves forward." (p. 35, Dellenbaugh)

The angle at which sailing is important. A 45 degree angle to the wind is the most effective angle.

Wind is what propels a sailing ship so weather has a large impact on the craft. Certain weather conditions are not suitable for sailing or specific crafts.

How to Cite this Page

MLA Citation:
"Physics of Sailing." 28 Feb 2020

Need Writing Help?

Get feedback on grammar, clarity, concision and logic instantly.

Check your paper »

Essay about Physics of Sailing

- The Hull of the boat is the frame which keeps the boat and its crew floating in the water. The mast is the tall pole that sits vertically near the center of the hull, the mast is what the sails are attached to to keep them suspended and straight. The boom is a large pole attached to the bottom part of the mast which is able to rotate up, down and side to side. The sails attach to the boom and the mast then the person controlling the main sail moves the boom around to change the direction and tension in the mainsail....   [tags: physics sport sports boating sail boat]

Free Essays
1562 words (4.5 pages)

Essay about Stability of a Sailing Kayak

- "Strippers" they are often called, relate to the method of boat building is old and well perfected. It basically involves setting up a series of molds and then wrapping strips of wood around them. More specifically, I'm mostly using the method outlined in the book Kayakcraft which is a great set of instructions for anyone wanting to take on this type of project. The wood for this boat is clear cedar that has been ripped into 3/4" x 1/4" strips. Each of those then get a concave and convex edge. This a great method because then each strip fits together perfectly at any angle seen on the plans....   [tags: physics kayak sport sports]

Free Essays
642 words (1.8 pages)

Physics of Baseball Essay

- Finding and understanding the sweet spot on a wooden bat. When you strike a bat against a ball it sends vibrations, much like the vibrations acting on airplanes or bridges, which travel in waves through the bat. This motion is important to understand because every vibration the bat experiences takes energy away from the ball's speed as it leaves the bat. If you hit the ball at a bat's "nodes", the frequencies (each bat vibrates at several low and high frequencies at once, which is like the harmonics of stringed instruments) cancel out and since this happens you don't feel the sting in your hands that you experience when you hit the ball at different points on the bat....   [tags: physics sport sports baseball]

Free Essays
630 words (1.8 pages)

Sailing to Byzantium Essay

- Sailing to Byzantium In W.B. Yeats, “Sailing to Byzantium” the narrator is an older man looking at his life with detest as the way it appears now. He is holding resent for the way the young get to live their lives and how he lives his now. The narrator is dealing with the issue of being older and his sadness of worth in this life, and who is later able to come to terms and accept his life. In “Sailing to Byzantium” the poem is broken up into four stanzas, each describing a different part of the voyage and the feeling associate with it....   [tags: W.B. Yeats Sailing to Byzantium Essays]

Research Papers
1169 words (3.3 pages)

Essay about Yeats’ Sailing to Byzantium

- Yeats’ Sailing to Byzantium       In "The Circus Animals' Desertion," W. B. Yeats asserted that his images "[g]rew in pure mind" (630). But the golden bird of "Sailing to Byzantium" may make us feel that "pure mind," although compelling, is not sufficient explanation. Where did that singing bird come from. Yeats's creative eclecticism, blending the morning's conversation with philosophical abstractions, makes the notion of one and only one source for any image implausible: see Frank O'Connor's comments on the genesis of "Lapis Lazuli," for example (211-22)....   [tags: Yeats Sailing Essays]

Research Papers
777 words (2.2 pages)

The Physics of the Arc Essay

- ABSTRACT Several researchers have devoted efforts on studying physics of arc and descriptive models are used to explain many arc welding related phenomena. However, due to the subject complexity, doubts still emerge about the mechanisms of some phenomena related to the arc. For instance, the description about electromagnetic interactions with the arc, which governs the arc trajectory and lead to plasma jet and arc blow formation, seems to be yet controversial. Thus, the present study aimed a better understanding of these phenomena....   [tags: Physics ]

Research Papers
1244 words (3.6 pages)

The Physics of Fishing Essay

- The Physics of Fishing The use of a boat while fishing and some of the physics applicable to boating will be included in exploring the various ways physics applies to the sport of fishing. Other topics will include the fishing rod, fishing lure, casting, and the fish itself. The boat floats on the water according to Archimedes Principle which states an immersed object is buoyed up by a force equal to the weight of the fluid it displaces. The force applied downwards by earth’s gravity coupled with the upward force of buoyancy allows the boat to float....   [tags: Physics ]

Research Papers
871 words (2.5 pages)

Life of the Soul Revealed in Sailing to Byzantium and Shadows Essay

- Life of the Soul Revealed in Sailing to Byzantium and Shadows         The view of death from an aged individual can be one of acceptance of his life’s end or one of mystified wonder over the immortality of the soul. Both William Butler Yeats and David Herbert Lawrence take the latter view in their respective poems, "Sailing to Byzantium" and "Shadows." By viewing death as a continuation of their soul’s life in a different realm of being, they provide a comforting solution to the fear that death may be the end of their existence....   [tags: Sailing Byzantium Essays]

Research Papers
2589 words (7.4 pages)

Essay about Forces in a Rolling Boat

- Every boat has a degree of roll from which she can no longer recover. Two forces are locked in combat for a ship about to capsize: the downward push of gravity and the upward lift of buoyancy. Gravity is combined with the weight of the vessel and everything in board-crew, cargo, fishing gear- seeking the center of the earth. Buoyancy is the force of all the enclosed air in the hull trying to rise above water level. On a evenly balanced and stable ship, these two forces are equal and cancel out each other, but all of this changes when a boat gets shoved over her side....   [tags: Physics Boating]

Free Essays
385 words (1.1 pages)

Essay on Sailing

- Sailing "People either love it, or they hate it," Fred proclaimed again, for the umpteenth time. His reddish face almost glowed against the gray sky. The combination of giddy grin, round cheeks, and fine, yellow, tousled hair yielded a face far too boyish for a man in his mid-fifties. But the always-present twinkle in Fred's eye was ever so slightly diminished today, and I knew why: he feared that his intuition might be mistaken and that I might not, after all, take to today's activity....   [tags: Personal Narrative, Autobiographical Essay]

Research Papers
1309 words (3.7 pages)

Beginners and experts should watch the weather conditions and follow weather broadcasts before they go sailing. One way to find out about weather conditions is through NOAA, the National Oceanographic and Atmospheric Agency. You can get your local forecast at their website, One method of telling the wind level before going on a sailing trip is by using the Beaufort scale.

Wind is caused by the movement of air due to warming caused by radiation. The sun warms the air. Warm air rises and cool air falls causing a circulation of air in the atmosphere. The radiation from the sun also warms the ocean and the land. The land looses its heat slower than the ocean does and therefore stays warmer longer. An offshore breeze caused by the warm air moving out to take the place the cooler out at sea. "A breeze that's blowing from the shore onto the water (such as a high-pressure wind) is generally oscillating. As you get closer to shore, the wind is puffier and shiftier and the water is smoother."(pg.183, Dellenbaugh)

One of these forces that the water has on the boat is drag. The boat must push through the water moving the water in front of it out of its way. "As the boat picks up speed, she creates waves, and these rather than the surface friction becomes the major part of the drag at higher speeds." (pg.7, Brewer) Sailing ships hull heel, an "athwartship inclination of the vessel" (pg. 208, Brewer),when they are moving faster, which increases drag on the ship. Most of the time the ship is also tipped slightly to the side instead of completely perpendicular to the water. This is due to the angle at which the boat is sailed into the wind ane the force the wind has on the ship. This difference in angle from the vertical also causes more drag on the ship.

Water has the another effect of determining the maximum speed of a ship. "When a boat which does not plane moves, it creates two waves which become further apart the faster the boat moves. At a certain speed, the distance between the wavecrests is close to the waterline length of the boat and the two crests are situated near the ends of the waterline shape of the boat." (pg. 327, Bond)

Now that you now how the boat stays afloat and is propelled through the water you need to be able to maneuver it. Vectors are used in manuevering a sailing ship. Vectors are described by both a magnitude and a direction. In the case of a ship, it is the speed of the ship and the direction the ship is going.

Sailing directly into the wind is difficult if not impossible. The wind is needed to propel the ship forward but a wind directly on the front of the ship will not be caught by the sail. The most efficient angle at which to be sailing into the wind is a 45 degree angle. At times, your destination will be in the same direction that the wind is coming from. To handle this, you will need to tack. Tacking is sailing back and forth at an angle to your destination, instead of taking the direct route to that destination.


Bond, Bob, The Handbook of Sailing: A complete Guide to

All Sailing Techniques and Procedures For the Beginner And the

Experienced Sailor, 1995, Alfred A. Knopf, New York

Brewer, Ted, Ted Brewer Explains Sailboat Design, 1985,

International Marine Publishing Co., Camden, Maine

Dellenbaugh, David and Brad Dellenbaugh, Small Boat

Sailing: A Complete Guide, 1990, Sports Illustrated, New York

Dent, Nicholas, How To Sail: a practical course in boat

handling, 1978, Orbis Publishing Limited, London

National Oceanigraphic and Atmospheric Administration, , March 24, 2005, National Oceanigraphic and

Atmospherical Administration, U.S. Department of Commerce

Serway, Raymond A. and John W. Jewett, Jr. , Physics for

Scientists and Engineers , 2004, Thomson Brooks/Cole, Belmont, CA

Werner, Doug, Sailor's Start-Up: A Beginner's Guide to

Sailing, 1994, Tracks Publishing, San Diego, CA
Return to