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Require physics help
USSEnterprise:
One of the few extracurricular activities I am involved in at school is the Cardboard Canoe team. This involves competing in a series of races against other cardboard canoes. The first part of the competition is based on a 3 minute verbal and visual presentation (no powerpoint allowed.) I would like to, for this presentation, to find out how fast our boat is capable of going, based on the mass of the loaded boat, the mass of the paddle, and the amount of force being exerted on the water by the paddle. My estimates for these are:
mass of boat: 135kg
Mass of paddle: 5kg
Force being exerted on water: Approx 20 lbs or about 90N per stroke
There is only one paddler per boat, with a single, double sided paddle.
Grasshopper:
You need a lot more information to do the calculation. For a start the effect of water and air resistance, both of which (I believe) go up exponentially with speed, and both of which are dependent to a degree on the shape of the boat.
Once the drag effect of air and water resistance equals the force exerted by the paddle, the canoe will stop accelerating. But calculating the speed at which that happens will involve a pretty advanced engineering calculation and a lot more variables than you've given.
Ed_McCarron:
--- Quote from: Grasshopper on May 12, 2007, 12:13:20 pm ---You need a lot more information to do the calculation. For a start the effect of water and air resistance, both of which (I believe) go up exponentially with speed, and both of which are dependent to a degree on the shape of the boat.
--- End quote ---
This is physics class. Aren't we allowed to assume we're in that perfect physics world where theres no friction?
Seriously, you'd need to know the mass of the paddler, water displaced, surface area under water, shape of the canoes frontal area, temperature of the water, density of water at that temp, etc, etc, etc.
Tons of variables.
Which ones do they let you neglect?
shardian:
That is more of a fluid mechanics problem. Definitely more complicated than a simple high school physics problem. I might have my fluids book sitting around - I'll look today.
USSEnterprise:
Probably a nevermind then. One part of the presentation is to explain the "mathematics and physics" of the design. I need to figure some information out for that.
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