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World of Engineering Profile picture
@engineers_feed
Dec 22, 2021 • 1 tweets • 1 min read • Read on X
The original patent from 1891 for a toilet paper roll shows the correct rolling direction, in case you ever doubted. Image

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More from @engineers_feed

World of Engineering Profile picture
Jul 16
GPS is in 6 billion devices.
Almost nobody knows how it actually works.
Here's the full story, including the 5 problems engineers had to solve first. [1/7]
THE BASIC PRINCIPLE
Your GPS receiver picks up signals from at least 4 satellites simultaneously.
Each signal carries two things: the satellite's exact position, and the exact time the signal was sent.
Your receiver compares the sent time to the received time.
Speed of light × time difference = distance to that satellite.
With distances to 4 satellites: your position in 3D. [2/7]
PROBLEM 1: TIME
The calculation requires knowing the exact time to nanosecond precision.
Light travels 30 cm per nanosecond. 1 microsecond of error = 300 metres of position error.
Solution: atomic clocks on every satellite (each GPS satellite carries 4, worth ~$400,000 each). [3/7]
Read 8 tweets
World of Engineering Profile picture
Jun 21
6 times in history, engineers said "don't do this."
They were overruled.
People died. [1/7]
1. CHALLENGER, 1986
Roger Boisjoly warned that O-rings would fail in cold temperatures.
Management launched anyway.
73 seconds. 7 crew members. [2/7]
2. TITANIC, 1912
Alexander Carlisle designed the ship for 64 lifeboats.
The White Star Line approved 20 to avoid "cluttering the deck."
1,517 dead. [3/7]
Read 7 tweets
World of Engineering Profile picture
Feb 3, 2024
The 10 greatest Engineers of all time:
1.Archimedes
Archimedes of Syracuse (c. 287 – c. 212 BC) was a Greek mathematician, physicist, engineer, astronomer, and inventor from the ancient city of Syracuse in Sicily. Image
2.Leonardo Da Vinci
Leonardo di ser Piero da Vinci (1452–1519) was an Italian polymath of the High Renaissance who was active as a painter, draughtsman, engineer, scientist, theorist, sculptor, and architect. Image
Read 11 tweets
World of Engineering Profile picture
Jan 21, 2023
12 basic components of a building structure:

1.Roof
2.Parapet
3.Lintels
4.Beams and slabs
5.Columns
6.Damp proof course (DPC)
7.Walls
8.Floor
9.Stairs
10.Plinth Beam
11.Plinth
12.Foundation

🧵
1. Roof
The roof forms the topmost component of a building structure. It covers the top face of the building. Roofs can be either flat or sloped based on the location and weather conditions of the area.
2. Parapet
Parapets are short walls extended above the roof slab. Parapets are installed for flat roofs. It acts as a safety wall for people using the roof.
Read 13 tweets
World of Engineering Profile picture
Jan 20, 2023
The 5 main components of an aircraft ✈️:

1. Fuselage
The fuselage is one of the major aircraft components. Its long hollow tube, also known as the body of the airplane, holds the passengers along with cargo.
2. Wings
Also known as foils, are one of the aircraft parts that are most imperative for flight. The airflow over the wings is what generates most of the lifting force necessary for flight.
3. Empennage
The empennage is located at the tail end of the aircraft. Its two main components, the rudder and elevator, help with the stability of the plane.
Read 5 tweets
World of Engineering Profile picture
Jan 19, 2023
Valve, in mechanical engineering, device for controlling the flow of fluids (liquids, gases, slurries) in a pipe or other enclosure.

Different types of valves:
Globe valve: It operates by reciprocating action of disc or plug. The disc or plug moves to or away from the seat thereby stopping the fluid flow or allowing the fluid to flow. Pressure drop in the globe valve is high.
Gate valve: Gate valve functions by the reciprocating action of disc in its body. It can have a single disc or double disc. It is used for shut off operation. In double disc valve shut off is good.
Read 17 tweets

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