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PHYSICAL QUANTITIES AND MEASUREMENT
Table of Contents
What are physical quantities?
In physics, a physical quantity is any physical property that can be quantified, that is, can be measured using numbers.
Examples of physical quantities are mass, amount of substance, length, time, temperature, electric current, light intensity, force, velocity, density, and many others.
Q.1 What is physics? Also, describe its important branches?
PHYSICS :> The branch of science that deals with the study of properties, energy, and their mutual relationship is called physics”
Some important branches of physics are given below
1. Mechanics:-It deals with the motion of bodies under the action of the force.
2. Heat and thermodynamics:-It deals with the study of nature, and its properties. and uses of heat energy. And also deals with the transformation of heat energy from one to another form.
3. Optics:- it deals with the prorogation, reflection, refraction, dispersion, and wave properties of light.
4. Electricity and magnetism:- it deals with the study of charges at rest as well as in motion.
5. Atomic physics:-it deals with the structure and properties of an individual atom.
6. Nucleus physics:- it deals with the structure and properties of the nuclease of an atom.
7. Solid-state physics:-it deals with the properties of matter in solid-state.
8. Particle physics:- it deals with the study of elementary particles.
9. Plasma physics:-which is the fourth state of matter. And occurs in an ionized state.
10. Quantum physics:-quanta is studied in this branch which is the discrete and individual particle of energy.
11. Semiconductor physics:- whose properties lie b/w conductor and insulator.
12. Astrophysics:- it deals with the study of heavenly bodies.
13. Biophysics:- the study of biology based on the principle of physics is called biophysics.
14. Geophysics:- it deals with the study of the earth and atmosphere.
15. Health physics:- it deals with the study of diseases and their treatment.
Q.2 defines measurement, unit, and magnitude?
Measurement:-the comparison of an unknown quantity with some standard is called measurement.
Unit:-the standard with which things are compared is called unit-meter, kg, second.
Magnitude:- A number with a proper unit is called magnitude. eg 3kg is magnitude.
Q.3 what is meant by physical Quantities? Also, explain basic and derived quantizes?
Physical Quantity:- Those quantities which can be measured are called physical quantities.
Basic quantities:-those physical quantities which are not derived from other quantities and but other quantities are derived from are called basic quantities. These are seven in number. The units of basic quantities are called basic units in the opposite table the units, quantities are seven and symbols.
