Posted by sandhu on .
A 7200 lb airplane lands on an aircraft carrier with a speed of 72 ft/s. The plane is caught by an elastic band (k=998 lb/ft) that has an initial stretch of 5.6 feet. What is the maximum distance the band is stretched?

Physics 
drwls,
(1/2)MV^2 = (1/2)k X^2
Solve for X
The mass M of the airplane must be in slugs when using this formula, since ft and lb are used for distance and force. 7200 lb weight = 223.6 slugs 
Physics 
sandhu,
It is a timely help.Thanks

Physics 
sandhu,
Should the initial stretch of 5.6 ft be added to X to find the maximum distance the band is stretched?