Inventions and Discoveries Notes

Electricity has always existed in nature.
Some fish use electric shocks to hunt.
Amber, known as "electron" by the Ancient Greeks, can produce electricity.
Scientists have studied electricity since ancient times.
A document from 1000–1 BCE in India describes how to make an electric cell (part of a battery).
In 1947, Pakistan produced 60 MW of electricity; by 2020, this increased to 37,402 MW.
Electricity usage became widespread in the late 19th century after Thomas Edison invented the light bulb and built power stations.
Edison's work enabled electricity to power heating and machines.
Before Pakistan's creation in 1947, private companies owned power stations, but limited cable infrastructure restricted electricity access.

Alexander Graham Bell, a British engineer, invented the phone.
Bell discovered that wires could copy sounds while experimenting with a piano.
He initially tested short wires between rooms.
Bell improved sound clarity for voice transmission.
In 1876, he connected wires between two houses a few miles apart.
Bell created a phone with separate speaking and listening parts.
He then started a telephone company, establishing telephone exchanges to link buildings.

Carts have existed for thousands of years, initially animal-pulled.
In the 19th century, steam engines powered carts, using coal or wood to heat water into steam.
Karl Benz, a German engineer, is credited with creating the first petrol cars.
Benz's car, the Motorwagen, was a three-wheeled vehicle.
He opened a car factory in 1888.
Early cars resembled carts with engines.
By the 20th century, mass production in American car factories lowered costs.
Initially, cars were exclusive to the wealthy, starting from the Model T.
Mahindra and Mahindra opened the first car factory in Mumbai in 1945; prior to that, cars were imported.

A camera uses a small hole and lens to let in light.
Light reflects from objects, passes through the lens, and forms an inverted image inside the camera.
Mozi (Mo Ti) in 5th century BCE China, made similar pictures.
Ibn al-Haytham in 10th century CE Persia (now Iraq), used reflected sunlight through a hole to study vision.
Ibn al-Haytham demonstrated that the pupils of our eyes function like a camera lens.
In 1826, a French scientist captured a camera picture on a metal plate coated with chemicals.
Improved lenses led to clearer pictures.
In 1885, George Eastman used plastic film instead of metal plates.
Images were stored on the film and printed on special paper.

Early attempts to fly mimicked birds, including kites, feathered wings, and hot air balloons.
In the 9th century in Spain, Abbas Ibn Firnas created an early glider but crashed.
The Wright Brothers in the USA built the first engine-powered airplane.
First, they tested kites and gliders and learned how to make them stay up in the air.
They tested ways to make them start and stop.

Early 20th century technologies: still and moving picture cameras, gramophones, phones, and radios.
Scientists aimed to transmit moving pictures through the air.
In 1884, Paul Nipcow created a spinning disc with holes to scan pictures.
Forty-five years later, John Logie Baird made a spinning disc "televisor" that could scan and play sounds alongside pictures.
Baird transmitted moving images along wires to a special TV set.
New electronic methods enabled transmission of moving pictures and sounds through radio waves.
The first long-distance public television broadcast was made from Washington DC on April 7, 1927.
The first live broadcast of Pakistan Television was on November 26, 1964, in Lahore.

People sought ways to perform calculations quickly since ancient times.
The astrolabe (150 BCE) calculated movements of celestial bodies.
Later machines were developed for calculations.
In 1822, Charles Babbage designed a mechanical computer with wheels and gears for astronomy and navigation calculations.
Electrical computers emerged in the 20th century and were programmable.
The world’s first electronic, digital, programmable computer was made in England and named Colossus.
During World War II, the British used Colossus to decode German radio messages.
Scientists used Babbage's notes and parts to build his “Difference Engine," which is now in the Science Museum in London.