Final answer:
The ease of moving a pencil in the middle compared to the end is due to torque. Torque is the rotational equivalent of force, and its magnitude depends on both the force applied and the distance from the point of rotation. When the pencil is displaced at the end, the torque produced by its weight is greater, making it more difficult to move.
Step-by-step explanation:
When it comes to moving a pencil, it is easier to move it in the middle rather than at the end due to a principle called torque. Torque is the rotational equivalent of force, and it depends on both the force applied and the distance from the point of rotation. In this case, the pencil's weight produces a torque that opposes the displacement of the pencil.
When the pencil is displaced at the end, the torque produced by its weight is larger compared to when it is displaced in the middle. This makes it more difficult to move the pencil at the end because a greater force is required to overcome the larger torque. On the other hand, displacing the pencil in the middle results in a smaller torque, making it easier to move.
Therefore, the distribution of weight and the distance from the point of rotation affect the ease of movement for the pencil.