Physics and the World of Other Sciences and Knowledge.
An X-ray at the hospital, a scoreboard on the field, an e-mail on your phone: which of the three is a gift of physics? All three. This section of the book walks through the fields where physics has quietly built the tools.
1. The base under other sciences
Physics is the foundation of the other branches of science. As its laws developed, a new branch was born from them: biophysics.
In chemistry, physics discoveries about atomic structure, radioactivity and X-rays brought a revolution. Mathematics is the language of physics here: its theories are completed through mathematical concepts, so mathematics is a powerful tool in developing theoretical physics.
In biology the electron microscope helped reveal the structure of the cell, and X-rays helped reveal the structure of nucleic acids. In astronomy Galileo's telescope helped us learn about the heavens, and the radio telescope played an important role in discovering quasars (Quasars) and pulsars (Pulsars).
2. Technology and medicine
The book names four main branches of technology: information, agricultural, medical and space technology. Electromagnetic induction, discovered by Faraday, is a base of technology; it is what led to generators, motors and transformers.
Geophysical surveys help discover oil fields. In a hydroelectric plant the potential energy of water becomes mechanical energy and then electrical energy. In a nuclear reactor, the nuclear energy released by fission is used to generate electricity.
Run the two power stations and follow the path the energy takes to become electricity.
energy pathpress run
Electricity from water and from atoms
Medical science uses X-ray, ultrasonography, CT scan, MRI, ECG, endoscopy, radiotherapy, ETT, angiography and isotopes, all gifts of physics. Radiotherapy, which uses radioisotopes, treats cancer and other diseases; X-rays are used to diagnose them.
Now the list is a hospital room. Switch the machines on one at a time.
hospitaltap a machine
Physics' gifts in one room
Four discoveries, four tools. Cover the right column and say the tool first, then tap the row.
matchEach tool has one job.
Which tool found what?
discovery
tool
Quasars and pulsars
radio telescope
Cell structure
electron microscope
Nucleic acid structure
X-ray
Oil fields
geophysical survey
The radio telescope played an important role in discovering quasars and pulsars. Galileo's telescope was the one that opened up the heavens.
The electron microscope helped reveal the structure of the cell.
X-rays helped reveal the structure of nucleic acids.
A geophysical survey helps discover oil fields.
3. Farms, society and the playing field
Agriculture changed greatly for two reasons. One, a botanist's discovery: plants make food using energy from sunlight. Two, new machines and the mechanisation of farming.
In sociology, the telephone, television, telex, e-mail, fax, internet and satellite channels let us contact the whole world in very little time. In sports, floodlights allow play at night, timers control time, scoreboards show the result, and speedometers measure speed.
Now drop seven examples into their seven fields.
sort themThink who uses the tool.
Which field, which gift?
Pick up a chip, then drop it in a field's box. Ask yourself: who uses this tool?
Right. Next one.
Not yet. Think about whose hands that tool ends up in.
All in place. The electron microscope shows the cell's structure. The radio telescope finds quasars and pulsars. Discoveries about atomic structure brought a revolution in chemistry. Mathematics is the language that completes theories. MRI is part of medical technology. The scoreboard shows the result of a game. E-mail reaches the whole world in very little time.
Six cards: the field on the front, the book's example on the back. Say it aloud before you turn one over.
fields and examplesSay it first.
Recall the example
FieldBiology
ExampleThe electron microscope for the cell's structure, X-rays for the structure of nucleic acids.
FieldAstronomy
ExampleGalileo's telescope; the radio telescope for quasars and pulsars.
Which instrument helped biologists learn the structure of the cell?
A radio telescope serves astronomy, not the study of cells.
An ECG records the heart's activity; it does not show the structure of a cell.
Right. The electron microscope revealed the structure of the cell.
A thermometer measures temperature; it is not a tool for seeing cells.
The second is about pairing a tool with its discovery.
check yourselfpick one answer
Question 2
What is the order of energy change in a hydroelectric plant?
This is a nuclear reactor, where the energy of fission is used, not a hydroelectric plant.
Right. The water's potential energy becomes mechanical and then electrical energy.
This order is reversed; a hydroelectric plant yields electrical energy, it does not start with it.
It is the water's potential energy that works here, not chemical energy.
In the last one, read every option carefully.
check yourselfpick one answer
Question 3
Read these statements about physics in medicine: i. radiotherapy uses radioisotopes ii. X-rays are used in diagnosis iii. the CT scan is not a gift of physics
i. Radiotherapy uses radioisotopes ii. X-rays are used in diagnosis iii. The CT scan is not a gift of physics
Right. i and ii are both in the book: radiotherapy uses isotopes and X-rays serve diagnosis; iii is false.
Taking iii says the CT scan is not physics' gift, but the book lists it among them.
ii holds but iii is false, since the CT scan is physics' gift; and i holds too.
iii is false, so all three cannot hold together.
The whole section on six cards.
cut from the notetap to turn over
Six cards
QuestionWhich new branch arose from the development of the laws of physics?
AnswerBiophysics.
QuestionThe use of which ray helped reveal the structure of nucleic acids?
AnswerX-ray.
QuestionWhich instrument played an important role in discovering quasars and pulsars?
AnswerThe radio telescope.
QuestionWhich phenomenon discovered by Faraday underlies generators, motors and transformers?
AnswerElectromagnetic induction.
QuestionWhat is used in radiotherapy for cancer?
AnswerRadioisotopes.
QuestionFor which two reasons did agricultural technology change greatly?
AnswerA botanist's discovery (plants make food using sunlight) and new machines with mechanisation.
Source: Physics 1st Paper, Classes 11-12 (NCTB), Chapter 1 “Physical World and Measurement”, section 1.4.