Angular momentum

1.Angular momentum - it is the opposite force to torque.Refer to figure 1 :

Figure 1 : Shows the opposite direction of both torque and angular momentum.The upward arrow indicates the angular momentum,while the downward arrow indicates torque.

 Figure 2 : The upward arrow indicates the torque ,while the downward arrow indicates angular momentum.

 2. Hence,this is the idea,of the figure 3 below :

Figure 3 : Shows gyroscope that remains upright while spinning.This is due to its angular momentum.

3.Refer figure 4

 

Figure 4 : The angular momentum is the same at every point on an orbit.When it is closer,it will increases the speed.This is the ideof the figure 5 below :

 

Figure 5 : When the angular momentum get closer (that the hand is close to the volunteer body) the spinning rate increases indicates the increase in speed.Both,angular momentum and moment inertia are inter-related in this case.

The moment Inertia

1. The moment inertia - it is an object resistance to change its rotation.

2. The SI unit : Kgm² (mass x length² )

3.Factor that effect the moment of inertia :
a. The mass of the body / object.
b.The distribution of the mass throughout the body.Hence,two body with the same mass may possess different moment of inertia.See figure 1 and 2

Figure 1 : Drivers reducing their moments of inertia  to increase their rate of rotation.

Figure 2 : Noted that,the angular velocity ( the movement / speed of body in rotaional shape ) increases as the distance from the central axis being reduced.