1. Understanding Force

A force is a push or pull that acts on an object, causing it to move, stop, or change direction. It is a vector quantity, meaning it has both magnitude (strength) and direction.

Formula for Force:

$$F=m\times a$$

Where:

• $F$ = Force (measured in Newtons (N))
• $m$ = Mass of the object (in kilograms (kg))
• $a$ = Acceleration (in m/s²)

📌 Example:
If a 5 kg object is pushed with an acceleration of 2 m/s²:

$$F=5\times 2=10N$$

So, the applied force is 10 Newtons.

✅ Key Point: A greater force or a lighter object results in faster acceleration.

2. Types of Forces

Forces are classified into two main types:

A. Contact Forces (Require Physical Contact)

1️⃣ Applied Force (Fₐ) – A direct push or pull on an object.

• Example: Pushing a shopping cart.

2️⃣ Friction Force (Fₓ) – A force that resists motion between two surfaces.

• Example: A car slowing down due to road friction.

3️⃣ Normal Force (Fₙ) – A support force exerted by a surface.

• Example: A book resting on a table.

4️⃣ Tension Force (T) – A force in ropes, strings, or cables.

• Example: Pulling a rope in tug-of-war.

5️⃣ Air Resistance – A force that opposes objects moving through air.

• Example: A parachute slowing down in the sky.