A door is opened by pushing inward
explain in terms of torque why this is most easily accomplished when pushing at right angles to the door as far as possible from the hinge side of the door?
To explain why it is easiest to open a door by pushing at right angles as far as possible from the hinge side, we need to understand the concept of torque.
Torque is the rotational force that causes an object to rotate around an axis. In the case of a door, the axis of rotation is the hinge, and the force that we apply to the door creates torque. The magnitude of torque depends on two factors: the force applied and the distance from the axis of rotation.
When you push a door, the force you apply creates a torque that acts to rotate the door around the hinge. The distance from the axis of rotation (hinge) to the point where you apply the force is called the lever arm. The longer the lever arm, the greater the torque for the same amount of force.
Now, let's consider why pushing the door at right angles and as far as possible from the hinge side is advantageous. When you push at right angles, the force you apply is perpendicular to the lever arm, creating the maximum torque. This is because the perpendicular distance from the hinge to the point of force application is maximized.
On the other hand, if you push the door inwards but closer to the hinge side, the lever arm becomes shorter, resulting in a smaller torque for the same force applied. This makes it harder to open the door as you're not maximizing the torque.
In summary, pushing a door at right angles and as far as possible from the hinge side increases the lever arm, resulting in a greater torque for the same amount of force. This makes it easier to open the door.