Archimedes Principle PPT

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Archimedes Principle
Final Exam – Cardboard Regatta
Boat Race
• CARDBOARD REGATTA
– BOAT RACE
Presented By: Al Mugno
Northern Highlands Regional High School
Archimedes Principle
• Archimedes' principle is named after
Archimedes of Syracuse, who first
discovered this law in 212 B.C
• “An object partially or wholly immersed in a
liquid is buoyed up by a force equal to the
weight of the liquid displaced by the object”
• Any fluid applied a buoyant force to an object
this is partially or completely immersed in it: the
magnitude of the buoyant force equals the
weight of the fluid that the object displaces”
Archimedes Principle
Archimedes Principle - Why ships
float!!
Archimedes Principle
Buoyancy
The “upward” force
is acting on an
object due to the
displaced fluid
Archimedes Principle - Buoyancy
How can this Principle be applied to
creating and solving the Cardboard
Regatta Boat Challenge?
Videos
• http://science.howstuffworks.com/6540mythbusters-lets-talk-buoyancy-video.htm
• http://www.youtube.com/watch?v=U1YVZMifMM
Types of Boat Hulls
Types Of Boat Hulls
(Flat, Round, Multi, Vee)
Some Terms Associated with Ship Floatation
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Here are some of the important terms associated with ship floatation and an
accompanying diagram to clarify the same.
Draft – this refers to the depth from the water surface till the bottom-most
section of the ship immersed in water
Freeboard – this refers to the remaining height of the ship above the water
level
TPC – Tonnes per centimeter refers to the amount of mass which must be
added or removed from a ship so that its draft changes by one centimeter.
WPA – Water plane area of a ship is the area of the ship which the ship
occupies when immersed in water at the water plane
Reserve Buoyancy – a ship is meant to load cargo hence when the ship is
empty it must have ample space to take additional weights of cargo etc
without sinking and this is known as reserve buoyancy which is defined as
percentage of total volume
Read more:
http://www.brighthub.com/engineering/marine/articles/19774.aspx#ixzz1Joc
dzRNa
PAPER BOAT BUOYANCY
CHALLENGE
PROBLEM
Design a paper cardstock boat that will float in the water with the following
criteria:
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The boat maximum size will be 4” wide and 8” long and 3” deep (side of the boat)
are the dimensions
The boat must be designed to have buoyancy in water for the longest period of
time while holding 12 weights (#8 3” carriage bolts, 4 washers and 2 carriag bolt
nuts) in addition to the boat materials
Once the boat sinks ( this is any portion of the boat travelling below the waters
line/surface) the time stops.
You will place the weights in the boat and then put the boat into the tub of water
for testing
TIME:
You will have two class periods to design this boat and test it – due by the end of
next class Friday(testing will take place the last 20 minutes of the class)
PEOPLE:
You will work in groups of 2; the group of three will produce two boats of which
one will be tested.
PAPER BOAT BUOYANCY
CHALLENGE – cont.
• Materials:
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sheet of cardstock supplied
scissors, x-acto knife kit. Pencil or pen to mark measurements only
12” of supplied tape
Ruler - for measuring only not to be used in the boat materials
GRADING:
Two Grades:
First:
30 seconds is the minimum passing time =100A+
For every second less than this required minimum time you will
lose 5 pts.
(3 seconds/12 seconds = 85 B – lose 15 points)
Second:
The overall time/weight graduated scale based upon the weights and
times.
Greatest weight & time = 100A+ , second 96 A, ……..
It will count as a project grade of 50%
Q & A??
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