សិល្បៈ
សម្រស់ និង សុខុមាលភាព
សិប្បកម្ម
វប្បធម៌ និង ប្រវត្តិសាស្ត្រ
ការកម្សាន្ត
បរិស្ថាន
ម្ហូប និង ភេសជ្ជៈ
វិស្វកម្មបញ្ច្រាស
វិទ្យាសាស្ត្រ
កីឡា
បច្ចេកវិទ្យា
ប្រដាប់ដែលស្លៀក

The Life Raft That Works Either Way Up
A raft thrown from a sinking ship lands whichever way it falls. If it only works one way up, someone in cold water has to right it first.
Maria E. Beasley of Philadelphia filed on 17 January 1881 for improvements to the life-raft of her earlier US 226,264 (6 April 1880); US 258,191 is dated 16 May 1882. Flat, hollow metal floats with bevelled ends are hinged side by side so they fold flat for stowing and open into one plane; grated railings with rowlocks are hinged to swing up on either face; and air-tight provision compartments open from either side, so that "in the event of its being overturned in the water it can be instantly used without any delay in righting or adjusting it."
This rung works out how many people a set of floats will carry and builds a reversible model from bottles.
មធ្យម
About 3 hours
ការណែនាំ
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1
Buoyancy and people
Buoyancy and people
កំពុងផ្ទុកសៀវភៅ Jupyter…
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2
What keeps it up
What keeps it up
Archimedes' principle sets how much a float can carry. The embedded blueprint measures displaced water.
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3
Read US 258,191
Read US 258,191
The object is "to improve the raft described and claimed in my Letters Patent of the United States numbered 226,264, and dated April 6, 1880, so that it may be more readily used." The improvements consist "in making the ends of the floats of the raft with a bevel upon both sides, attaching the railings by hinges so constructed as to be erected securely upon either surface, and in forming doors and stoppers for the water and provision compartments that may be opened upon either side", sometimes with a double railing, "so that in the event of its being overturned in the water it can be instantly used without any delay in righting or adjusting it."
The floats A are "flat rectangular metallic floats, having both sides of the ends beveled", joined by hinges B, some with chambers C and stoppers D for provisions. Bars E hook across to hold the floats in one flat plane. Hinges G "capable of turning in both directions" carry a grated railing H with an upper rail J and rowlocks K; hinged gates L at the ends complete the enclosure. Seats rest on the gratings, and a flag-staff stands in rings on one gate. Folded, railings and gates lie parallel with the floats.
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4
Build a reversible model
Build a reversible model
Tie four capped PET bottles side by side into two pairs, and join the pairs along their length with loops of paracord through holes in two strips of plywood, so the pairs fold flat on each other like Beasley's hinged floats. Fix a light dowel rail to each long side on small hinges so it can be swung up on either face.
Float it in a bath or pond, load it with weights until the bottles are awash, and compare with the notebook. Flip it over, swing the rails, and load it again: it should carry the same either way up.
សម្ភារៈសម្រាប់ជំហាននេះ៖
ដប PET (ភេសជ្ជៈមានឧស្ម័ន)4 ដុំ
ខ្សែប៉ារ៉ាកត1 ដុំ
សន្លឹកឈើបន្ទះ1 ដុំ
ដែកគោលឈើរឹង1 ដុំ
បន្តោងទ្វារ4 ដុំ
ខ្ចៅឈើ16 ដុំឧបករណ៍ដែលត្រូវការ៖
ស្វានឥតខ្សែ
សំណុំក្បាលខួង
ជញ្ជីងឌីជីថលផ្ទះបាយ
ទម្ងន់5
5
A model raft that misbehaves
A model raft that misbehaves
Model raft troubleshooting.
Flow
Loading...
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6
History and honest limits
History and honest limits
**Maria E. Beasley** of Philadelphia filed on 17 January 1881; US 258,191 is dated 16 May 1882 and improves her US 226,264 of 6 April 1880. She claims hollow metal floats hinged to fold, with bevelled ends that ride either way up, and railings hinged to stand above either face.
**Honest limits.** Float sizes, raft mass and the reserve in the notebook are examples; real life-saving equipment must meet maritime standards.
សម្ភារៈ
6- កន្លែងទុក
- 1 ដុំកន្លែងទុក
- 1 ដុំកន្លែងទុក
- 1 ដុំកន្លែងទុក
- 4 ដុំកន្លែងទុក
- ខ្ចៅឈើកម្រៃ 10%16 ដុំកន្លែងទុក
ឧបករណ៍ចាំបាច់
4- 1 vendor sell this, none ship to you yetកន្លែងទុក
- កន្លែងទុក
- កន្លែងទុក
- កន្លែងទុក
ប្លង់ពាក់ព័ន្ធ
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Testing a Gold Crown with Water — Archimedes' Buoyancy and the Eureka Method
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CC0 សាធារណៈ
ប្លង់នេះត្រូវបានចេញផ្សាយក្រោម CC0។ អ្នកមានសិទ្ធិចម្លង កែប្រែ ចែកចាយ និងប្រើប្រាស់ដោយមិនចាំបាច់សុំអនុញ្ញាត។
គាំទ្រអ្នកបង្កើតដោយទិញផលិតផលតាមរយៈប្លង់របស់ពួកគេ ដែលពួកគេទទួលបាន កម្រៃជើងសារអ្នកបង្កើត កំណត់ដោយអ្នកលក់ ឬបង្កើតកំណែថ្មីនៃប្លង់នេះ ហើយបញ្ចូលជាការតភ្ជាប់ក្នុងប្លង់របស់អ្នកដើម្បីចែករំលែកចំណូល។