HELP!! Sailors need to consider the speed of the wind when adjusting the sails on their boat. The force F (in pounds per square foot) on a sail when the wind is blowing perpendicular to the sail can be modeled by the function F = 0.004v^2 where v is the wind speed (in knots).

Find the wind speed that will produce a force of 2.5 pounds per square foot on a sail.

Question

HELP!! Sailors need to consider the speed of the wind when adjusting the sails on their boat. The force F (in pounds per square foot) on a sail when the wind is blowing perpendicular to the sail can be modeled by the function F = 0.004v^2 where v is the wind speed (in knots).

Find the wind speed that will produce a force of 2.5 pounds per square foot on a sail.

anonymous · Answer

put F=2.5
2.5=0.004 v^2
2.5/0.004 v^2
625=v^2 
v=25 or -25(rej.)