Forces And Terminal Velocity

Forces And Terminal Velocity

1. Objects falling through a fluid eventually reach terminal velocity, when the resultant force acting on them is zero and they are moving at a steady speed

2. Weight is a force exerted on an object because of a gravitational force

3. Falling objects

   • Forces affecting an object falling
     • The weight of the object. This is a force acting downwards, caused by the object’s mass the Earth's gravitational field
     • Air resistance. This is a frictional force acting in the opposite direction to the movement of the object
   • 3 stages of falling
     • 1. At the start, the object accelerates downwards because of its weight. There is no air resistance. There is a resultant force acting downwards
     • 2. As it gains speed, the object's weight stays the same, but the air resistance on it increases. There is a resultant force acting downwards
     • 3. Eventually, the object's weight is balanced by the air resistance. There is no resultant force and the object reaches a steady speed, called the terminal velocity

4. W = m x g

   • W = the weight, measured in newtons (N)
   • m = the mass, measured in kilograms (kg)
   • g = gravitational field strength, measured in newtons per kilograms (N/kg)