With this information, you can calculate the quantity of feet per second 40 knots is equal to.

¿What is the inverse calculation between 1 foot per second and 40 knots?

Performing the inverse calculation of the relationship between units, we obtain that 1 foot per second is 0.014812095 times 40 knots.

Which is the same to say that 40 knots is 67.512394 feet per second.

Forty knots equals to sixty-seven feet per second. *Approximation

A foot per second is zero times forty knots. *Approximation