Learning Resources

Fun with Fundamentals Puzzler: Gone to the dogs

May 5, 2007

The angle between King’s and Summer’s leashes is 137°. With what force does Summer pull to counterbalance that of the other beasts?

Elisabeth Eitel

See the previous problem: A Stupid Dream.

To make a little extra spending cash, Finagle J. Wurme has taken a job as a dog walker.

When he meets up with his new clients, he’s dismayed to learn he’ll be walking three Irish Wolfhounds — Summer, Autumn, and King.

All is going well until they get to the dog park.

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When the three wolfhounds see all the other puppies playing, they start barking like mad and want to join in the fun. Try as he might, Finagle can’t control the three dogs and soon enough, each one is tearing off in a different direction, leaving poor Finagle stuck in the middle.

King pulls his leash with a force of 220 N and Autumn pulls her leash with a force of 170 N. Imagine Finagle’s feet are planted on the ground so he’s stationary and the angle of Autumn’s leash is not given.

The angle between King’s and Summer’s leashes is 137°.

With what force does Summer pull to counterbalance that of the other beasts?

Okay, show me the solution.

About the Author

Elisabeth Eitel

Elisabeth Eitel was a Senior Editor at Machine Design magazine until 2014. She has a B.S. in Mechanical Engineering from Fenn College at Cleveland State University.