Forces in Two Dimensions - Mission F2D4 Detailed Help


A flower pot that weighs 20.0 N is supported symmetrically by three cables that make an angle of 60.0 degrees with the horizontal. A single cable will pull upward on the flower pot with a force of ____ Newton. 

(Note: Numbers are randomized numbers and likely different from the numbers listed here.)


 

Definition of Equilibrium:
Equilibrium 
is the condition in which all the individual forces acting upon an object are balanced.


 
If a flower pot is at equilibrium, then the individual forces acting upon the pot are balanced. The net force is 0 Newton. In order for the net force to be 0 N, there must be a balance of both horizontal and vertical forces. If the flower pot is supported by cables, all the cables together must pull with sufficient enough upward force to balance the weight (the downward force of gravity) of the flower pot. Thus, if the pot weighs 100 N and there are four cables, the upward components of tension in each cable must together provide 100 N of upward force. If the cables are arranged symmetrically, then the weight of the pot is distributed equally among the four cables. Each of the four cables will have a vertical component of 25 N to supply the needed 100 N of upward force to balance the pot's weight.


 
The question asks to determine the amount of upward pull exerted by the cable. The word upward is critical to the question. The question is focused on the vertical component of tension in the sign - not simply on the total amount of tension in the sign.