--- ## Free fall motion/constant acceleration - When an object is in free fall it will experience both **air resistance and gravity**. However in most basic models we assume that the object is falling in **a vacuum** and therefore does not experience **air resistance.** - In this model all objects, regardless of weight **will hit the ground at the same time**. *(assuming they were dropped without any initial downwards acceleration at the same time).* - The "*acceleration due to gravity*" describes the acceleration that an object in free fall experiences **due to the force of gravity**. This constant acceleration is why objects in a vacuum will continue to fall **faster and faster over time**. In the real world **air resistance** eventually overcomes the force of gravity at some point preventing the object from accelerating *any further* this is known as the object's *terminal velocity*. - If an object is **in the air and has no other forces acting on it the only force it will feel is g, the acceleration due to gravity**. $\text{Acceleration due to gravity: }\space9.8\space\frac{m}{s^2}$ >[!danger] >**$\Large g$ or acceleration due to gravity is only the *magnitude* of acceleration, not the direction. Therefore you will have to specify a direction *(negative or positive)*.** *It will almoast always be negative* >[!quote] >##### Constant acceleration graph >- The **velocity** graph of an object in **ideal free fall** *(no air resistance)* will always be **linear and sloped downwards.** since the acceleration is constant and negative. >- From this we can extrapolate to say that **any object with constant acceleration will have a linear velocity vs time graph and an exponentially or parabolically curved position vs time graph** *(either upwards **or** downwards)*. --- ## Calculator <iframe src="https://amesweb.info/Physics/Free-Fall-Calculator.aspx" width="100%" height="4000"></iframe>