Question:
LectureNotes said an object is moving to the west at a constant speed. Three forces are exerted on the object. One force is 10 N directed due north, and another is 10 N directed due west. What is the magnitude and direction of the third force if the object is to continue moving to the west at a constant speed?
Answer:
To maintain a constant speed while moving to the west, the net force in the east-west direction should be zero. Since two forces are already acting in the north and west directions, a third force needs to be applied in the east direction to balance them out.
Given:
- Force 1 (10 N) directed north.
- Force 2 (10 N) directed west.
For the object to continue moving westward, the third force must balance the other two forces. We can visualize this scenario using vector components:
- The 10 N north force has no effect on the object’s east-west motion since it is perpendicular to this direction.
- The 10 N west force acts solely in the west direction.
The third force should be 10 N directed eastward to counter the 10 N west force. Therefore, the magnitude of the third force is 10 N, and its direction is east.