A small railroad car is pulled by a rope as shown in the sketch (top view). The force F that the rope exerts on the car has a component along the track and another component perpendicular to the track.
Judging from the diagram, the larger of these two components would be
1) along the track.
2) perpendicular to the track.
These components will be equal if
3) the rope makes an angle of 45 with the track.
4) the rope is pulled in a direction along the track, rather than at an angle to it.
5) they form an action-reaction pair on the car.
6) but they can never really be equal.
Question 2
The boat to make the fastest progress in its forward direction is boat
1) 1.
2) 2.
3) 3.
4) 4.
Boat 3 is not propelled in a forward direction because
5) the wind does not make impact with the sail.
6) there is no component of force parallel to the keel.
7) of air resistance on the front of the sail.
8) But it is propelled in a forward direction
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