Answer:
A force of 12.857 newtons must be applied to open the door.
Explanation:
In this case, a force is exerted on the door, a moment is performed and the door is opened. If moment remains constant, the force is inversely proportional to distance respect to axis of rotation passing through hinges. That is:
(Eq. 1)
Where:
- Force, measured in newtons.
- Proportionality ratio, measured in newton-meters.
- Distance respect to axis of rotation passing through hinges, measured in meters.
From (Eq. 1) we get the following relationship and clear the final force within:
(Eq. 2)
Where:
,
- Initial and final forces, measured in newtons.
,
- Initial and final distances, measured in meters.
If we know that ,
and
, then final force is:
A force of 12.857 newtons must be applied to open the door.