Introduction to physics

What is Physics?

The study of matter, energy, and the fundamental forces of nature, explaining how and why objects move or remain at rest and how different forms of energy interact with matter.

Who was Sir Isaac Newton?

An English physicist and mathematician (1642–1727) who developed the Three Laws of Motion and formulated the Universal Law of Gravitation.

Newton’s First Law of Motion

An object will remain at rest or in uniform motion unless acted upon by an external force. This is also known as the Law of Inertia.

Newton’s Second Law of Motion

The force $F$ acting on an object is equal to the mass $m$ of the object times its acceleration $a$. This is represented by the formula: $F = m \cdot a$

What is Physics?

The study of matter, energy, and the fundamental forces of nature, explaining how and why objects move or remain at rest and how different forms of energy interact with matter.

Who was Sir Isaac Newton?

An English physicist and mathematician (1642–1727) who developed the Three Laws of Motion and formulated the Universal Law of Gravitation.

Newton’s First Law of Motion

An object will remain at rest or in uniform motion unless acted upon by an external force. This is also known as the Law of Inertia.

Newton’s Second Law of Motion

The force $F$ acting on an object is equal to the mass $m$ of the object times its acceleration $a$. This is represented by the formula: $F = m \cdot a$

Newton’s Third Law of Motion

For every action, there is an equal and opposite reaction.

Universal Law of Gravitation

The gravitational force $F$ between two objects is proportional to the product of their masses $(m1, m2)$ and inversely proportional to the square of the distance $r$ between their centers. The formula is: $F = G \cdot \frac{m1 \cdot m2}{r^2}$, where $G$ is the gravitational constant (6.674 × 10⁻¹¹ N·m²/kg²).

Formula for Speed

Speed $v$ is calculated as distance $d$ divided by time $t$. The formula is: $v = \frac{d}{t}$

Formula for Acceleration

Acceleration $a$ is calculated as the change in velocity $(vf - vi)$ divided by time $t$. The formula is: $a = \frac{vf - vi}{t}$

Formula for Weight

Weight $W$ is calculated as mass $m$ times the acceleration due to gravity $g$ (9.8 m/s²). The formula is: $W = m \cdot g$

Kinetic energy $KE$ is calculated as one-half times the mass $m$ times the square of the velocity $v$. The formula is: $$