What is the value of gravitational acceleration on Earth?

The value of gravitational acceleration on Earth is approximately 9.8 metres per second squared (m/s²).

Gravitational acceleration, often denoted by the symbol \( g \), is the rate at which objects accelerate towards the Earth due to gravity. This value is crucial in physics as it affects everything from the motion of falling objects to the orbits of satellites. The standard value of \( g \) is 9.8 m/s², although it can vary slightly depending on where you are on the Earth's surface. For instance, \( g \) is slightly stronger at the poles and weaker at the equator due to the Earth's rotation and its slightly oblate shape.

To understand gravitational acceleration, imagine you drop a ball from a height. As it falls, it speeds up, accelerating at a rate of 9.8 m/s². This means that for every second the ball is falling, its velocity increases by 9.8 metres per second. So, after one second, its velocity is 9.8 m/s; after two seconds, it's 19.6 m/s, and so on, assuming no air resistance.

Gravitational acceleration is a fundamental concept in physics because it helps us predict how objects will move under the influence of gravity. It is also essential for calculating other important quantities, such as the weight of an object, which is the force of gravity acting on it. The weight can be calculated using the formula \( W = mg \), where \( W \) is the weight, \( m \) is the mass of the object, and \( g \) is the gravitational acceleration.

Understanding \( g \) also helps in analysing projectile motion, where objects are thrown or propelled into the air. By knowing the value of \( g \), we can predict the trajectory and landing point of the projectile, which is useful in various real-world applications, from sports to engineering.