Notes, summaries, assignments, exams, and problems for Physics

Matter exhibits both particle and wave nature. The derivation of the De Broglie equation establishes the fundamental relationship between these two natures of a particle.

Louis de Broglie's Hypothesis on Dual Nature

In 1924, the French physicist Louis de Broglie proposed that electrons also possess particle and wave characteristics, just as photons or light. According to his hypothesis, every particle exhibits dual characteristics. Furthermore, he indicated that the path of electrons is wavy, similar to light having a definite frequency. For this groundbreaking theory, De Broglie received the Nobel Prize in Physics in 1929.

The De Broglie Equation and Confirmation

The experiment of cathode-ray diffraction by George Paget Thomson and the Davisson–Germer... Continue reading "Deriving the De Broglie Wavelength Equation" »

ਪੰਜਾਬੀ ਵਿਆਕਰਨ: ਸੰਗਿਆਤੀ ਤੇ ਤਤਸਮ ਸ਼ਬਦ

ਪੰਜਾਬੀ ਵਿਆਕਰਨ ਵਿੱਚ ਸੰਗਿਆਤੀ ਸ਼ਬਦ ਅਤੇ ਤਤਸਮ ਸ਼ਬਦ ਦੋ ਵੱਖੋ-ਵੱਖਰੇ ਪਰ ਮਹੱਤਵਪੂਰਨ ਸੰਕਲਪ ਹਨ ਜੋ ਸ਼ਬਦਾਂ ਦੇ ਮੂਲ ਅਤੇ ਉਹਨਾਂ ਦੇ ਵਿਕਾਸ ਬਾਰੇ ਜਾਣਕਾਰੀ ਦਿੰਦੇ ਹਨ। ਆਓ, ਇਨ੍ਹਾਂ ਨੂੰ ਸਮਝੀਏ:

ਸੰਗਿਆਤੀ ਸ਼ਬਦ (Cognates)

ਸੰਗਿਆਤੀ ਸ਼ਬਦ ਉਹ ਸ਼ਬਦ ਹੁੰਦੇ ਹਨ ਜਿਨ੍ਹਾਂ ਦੀ ਉਤਪਤੀ ਇੱਕੋ ਹੀ ਮੂਲ ਭਾਸ਼ਾਈ ਜੜ੍ਹ (common... Continue reading "ਪੰਜਾਬੀ ਵਿਆਕਰਨ ਦੇ ਮਹੱਤਵਪੂਰਨ ਅੰਗ: ਸ਼ਬਦ, ਵਾਕ ਤੇ ਵਿਸ਼ੇਸ਼ਣ" »

Fundamental Concepts in Physics

The Atom

An atom is composed of electrons, protons, and neutrons.

Temperature

Temperature is the physical quantity that describes the sensation of cold or hot, directly related to the average kinetic energy of molecules. It represents the average kinetic energy of each molecule.

Heat

Heat is the transfer of energy from one body to another due to a temperature difference. It is a form of energy that can be perceived through temperature variations.

Types of Thermal Expansion

• Linear Expansion
• Surface Expansion
• Volumetric Expansion

Thermodynamics

Thermodynamics is the branch of physics that studies heat transfer and the conversion of energy into its various forms.

Laws of Thermodynamics

• Zeroth Law
• First Law
• Second Law

Zeroth Law

Electrostatics Fundamentals

This document covers key concepts in electrostatics, including properties of electric charge, Coulomb's Law, and electric fields.

Properties of Electric Charge

Here are four fundamental properties of electric charge:

1. Additivity of Charges: The total charge of a system is the algebraic sum of all individual charges present in the system.
2. Conservation of Charge: The total charge of an isolated system remains unchanged over time. Charge can neither be created nor destroyed, only transferred.
3. Quantization of Charge: The total charge of a body is always an integral multiple of a basic quantum of charge, denoted as 'e'. This means charge q can only exist as q = ±ne, where n is an integer (1, 2, 3, ...).
4. Interaction of Charges:

Biology Fundamentals

Genetics: DNA and RNA

• DNA: Double helix structure; carries genetic information. Bases pair A–T and C–G.
• RNA: Single strand; uses Uracil (U) instead of Thymine (T); assists in protein synthesis.

Cell Division

• Mitosis: Results in two identical daughter cells; essential for growth and repair.
• Meiosis: Results in four genetically different cells; produces gametes (sperm and egg).

Chromosomes

• Humans possess 23 pairs, totaling 46 chromosomes:
  • 22 pairs are autosomes.
  • 1 pair consists of sex chromosomes (X/Y).
• Sex determination: Males are XY; Females are XX.

Inheritance Principles

• Dominant Allele: Expressed even if only one copy is present.
• Recessive Allele: Expressed only when two copies are present.
• Use Punnett squares to predict trait outcomes

Thermodynamics

First Law of Thermodynamics (Law of Energy Conservation)

Energy cannot be created or destroyed; it can only change forms.

Formula: ΔU=Q−W

Where: ΔU is the change in internal energy of the system, Q is the heat added to the system, W is the work done by the system.

Explanation: The total energy in a closed system remains constant. Energy can be transformed from one form to another (e.g., heat energy to mechanical energy).

Second Law of Thermodynamics

Key Concept: The total entropy (disorder) of an isolated system always increases or remains constant.

Formulas:

Entropy Change for Reversible Process: ΔS=Qrev /T

Where: ΔS is the change in entropy. Qrev is the heat added in a reversible process. T is the absolute temperature. Qirr is... Continue reading "Thermodynamics and Simple Harmonic Motion" »

ਪੰਜਾਬੀ ਸ਼ਬਦ ਰਚਨਾ: ਅਗੇਤਰ ਅਤੇ ਪਿਛੇਤਰ

ਪੰਜਾਬੀ ਵਿੱਚ ਸ਼ਬਦ ਰਚਨਾ (Word Formation) ਦੇ ਦੋ ਪ੍ਰਮੁੱਖ ਤਰੀਕੇ ਹਨ: ਅਗੇਤਰ ਅਤੇ ਪਿਛੇਤਰ। ਇਹਨਾਂ ਦੀ ਵਰਤੋਂ ਮੂਲ ਸ਼ਬਦਾਂ ਤੋਂ ਨਵੇਂ ਸ਼ਬਦ ਬਣਾਉਣ ਲਈ ਕੀਤੀ ਜਾਂਦੀ ਹੈ।

1. ਅਗੇਤਰ (Prefixes)

ਜਿਹੜੇ ਸ਼ਬਦ-ਅੰਸ਼ ਮੂਲ ਸ਼ਬਦ ਦੇ ਸ਼ੁਰੂ ਵਿੱਚ ਲੱਗ ਕੇ ਉਸ ਦੇ ਅਰਥਾਂ ਵਿੱਚ ਤਬਦੀਲੀ ਲਿਆਉਂਦੇ ਹਨ ਜਾਂ ਨਵਾਂ ਸ਼ਬਦ ਬਣਾਉਂਦੇ ਹਨ, ਉਹਨਾਂ... Continue reading "ਪੰਜਾਬੀ ਵਿਆਕਰਨ: ਸ਼ਬਦ ਰਚਨਾ, ਸ਼੍ਰੇਣੀਆਂ, ਵਾਕ ਅਤੇ ਅਰਥ ਬੋਧ" »

1. ਨਾਮ (Noun) ਦੀ ਪਰਿਭਾਸ਼ਾ

ਵਿਆਖਿਆ:
ਨਾਮ ਉਹ ਸ਼ਬਦ ਹੁੰਦਾ ਹੈ ਜੋ ਕਿਸੇ ਵਿਅਕਤੀ, ਜੀਵ, ਜਾਨਵਰ, ਥਾਂ, ਵਸਤੂ, ਭਾਵਨਾ ਜਾਂ ਧਾਰਨਾ ਦੀ ਪਛਾਣ ਦਿੰਦਾ ਹੈ। ਸਧਾਰਨ ਤੌਰ ‘ਤੇ ਨਾਮ ਸਾਡੇ ਆਲੇ-ਦੁਆਲੇ ਦੀਆਂ ਚੀਜ਼ਾਂ ਨੂੰ ਪਛਾਣਨ ਅਤੇ ਬੋਲਣ ਲਈ ਵਰਤਿਆ ਜਾਂਦਾ ਹੈ।

ਉਦਾਹਰਨਾਂ:

• ਵਿਅਕਤੀ: ਅਮਨ, ਸਿਮਰਨ
• ਪਸ਼ੂ: ਕੁੱਤਾ, ਬਿੱਲੀ
• ਥਾਂ: ਪੰਜਾਬ, ਦਿੱਲੀ
• ਵਸਤੂ: ਕਿਤਾਬ, ਕੁਰਸੀ
• ਭਾਵਨਾ: ਖੁਸ਼ੀ,

.All material objects are composed of atoms. An atom consists of a nucleus and a vast region of space outside the nucleus. Electrons are present in the region of space outside the nuclues. Electrons are often removed from and a dded to an atom by normal everyday occurrences. The nucleus contains positively-chargedd protons and nuetral neutrons. These prtons and nuentrons are not removable or disturbable by usual everyday methods. One sure truth of this unit is that the porotn and neutron will remain within the nucleus of the atom.
Methods of charging:-friction:Having an excess of electrons thr rubber ballon is charged negatively.The shortage of electrons on the animal fur leaves it with a positive charge.-Induction: is a very common method of... Continue reading "Basic Principles of Electricity and Atomic Physics" »

By: accident, chance, hand, heart, law, mistake, no means, request, virtue of, in a good mood, private, return, time, brief, danger, difficulty, doubt, a hurry, a mess. On: purpose, a regular basis, schedule, strike, time (a tiempo), average, balance, condition, fire. At: a price, one time, risk, the age of, all cost, a glance, least. Of: member, remind, at a rate, a cause, approval, experience, get rid, habit. With: link, regret, sympathize, arguments, contact, concern, dealing, difficulty. To: explain, reply, access, addiction, belong, change, damage. For: life, once, real, a while, a reason, demand, hire. From: time to time, now on, memory, experience. Out: of place, of stock, of sight. Conductance: the amount of power - Conductivity: The... Continue reading "Understanding Energy and Electricity: A Comprehensive Guide" »