Finagle J. Wurme is getting ready to live one of his lifelong dreams — auditioning for a spot on David Letterman's Stupid Pet Tricks. Finagle's been training his Siamese cat, Thrasher, to ride a skateboard and things are going well. He's now ready to take Thrasher to the next level.

Finagle is busy constructing a short track with a loop built into the middle, for Thrasher to skateboard down on the big day. But he's not sure how high he needs to build the starting ramp for Thrasher to make it safely around the loop on his board.

Together, Thrasher and his skateboard weigh 15 lbs and the radius of the loop is 5 ft. Assume there's no friction on the track and kitty has perfect balance. How high must Thrasher start from to be able to make it safely around the loop without falling off due to gravity?

To be eligible for a prize, send your solution to msdeditor@penton.com by August 15, 2007. Please include contact info in all attachments. April's problem, solution, and prizewinner are also posted on our site, accessible through the yellow Archive button toward the bottom of the homepage.

Win a fun book

The winner of Problem #298 receives a copy of Henry Petroski's first book, To Engineer is Human: The Role of Failure in Successful Design. Petroski posits that technology evolves just as designs in nature — and outlines the characteristics that lasting designs share. This is a terrific read for any engineer.

• Examines great engineering failures that came before major successes

• Reviews several of the most infamous engineering failures in recent history