Torque

The first term that I choose to elaborate on is TORQUE. The reason for this is that the understanding of torque is fairly essential to understand other concepts.

In order to get an object to move we need to apply a Force on it. In simple words, we need to push it.
The force will move an object.

You will agree that if you desire to not just move an object, but to get it to roll (like a wheel), you will need to apply a force slightly differently. The force will ideally be along the edges of the object.

To understand this better, observe the way the kids who play on the streets with tyres and a stict keep hitting the tyre along the surface. This type of an action causes it to roll.

In short, the kids supply the torque for the motion of the tyre.

Lets go ahead and get one more observation listed.

You will notice that to get the tyre to more initially from a stationary position requires more torque than what is required by the tyre to continue moving once already set into motion. This is because of the initial inertia that one ahs to overcome.

The similar situation holds true for cars. They require greater torque to get into motion than to continue motion (unless you try to increase the speed of the car at a high rate – hit the accelerator hard!)

Cars are hence tuned in such a way that a higher torque is generated when they need to be set into motion. This is achieved by the use of gears.

With this initial brief on torque, we will now look at gears elaborately.