Table of Contents
Forces are all around us! When you push a door, kick a ball, or even just stand still, forces are at work. These notes will help you understand what forces are and how they affect objects in our daily lives.
1. What is a Force? #
A force is a push or pull that acts on an object. Forces can make things move, stop moving, or change direction.
Key Points About Forces: #
- Measurement: Forces are measured in Newtons (N)
- Direction: Forces always have both size (magnitude) and direction
- Contact Forces: Need objects to touch (like pushing a box)
- Non-contact Forces: Work without touching (like magnets)
2. Effects of Forces #
Forces can change objects in different ways. Here are the main effects:
Change in Motion #
- Make things start moving
- Make things stop moving
- Change speed
- Change direction
Change in Shape #
- Squash objects
- Stretch objects
- Bend objects
- Twist objects
Force Diagrams #
3. Types of Forces #
| Force Type | Description | Example |
|---|---|---|
| Gravity | Pulls objects toward the Earth’s center | A ball falling down |
| Friction | Resists motion between surfaces | Shoes gripping the ground |
| Air Resistance | Air pushing against moving objects | Parachute slowing down |
| Magnetic | Attraction or repulsion between magnets | Fridge magnets sticking |
4. Balanced and Unbalanced Forces #
When forces act on an object, they can either be balanced or unbalanced:
