Mass and weight are important ideas that help us understand how things move.

1. What They Mean:

   • Mass: This tells us how much stuff is in an object. It is measured in kilograms (kg).
   • Weight: This is the force that pulls an object down due to gravity. We measure weight in newtons (N). You can find weight using this formula: $W = m \times g$ Here, $g$ is about 9.81 meters per second squared (m/s²), which is how fast gravity pulls things down on Earth.

2. How They Affect Motion:

   • Heavier objects, or those with more weight, need more force to start moving or to speed up. This idea comes from Newton's Second Law.
   • For example, if a car weighs 1000 kg, it needs a force of 1000 N to go faster at a rate of 1 m/s².

3. Everyday Examples:

   • Think about a feather and a rock. The feather is light (low mass and low weight), so it falls slowly. The rock is heavy (high mass and high weight), so it falls quickly. This shows us how weight affects how things fall.

Knowing the difference between mass and weight helps us understand how things behave in the real world.