How Do You Determine When to Use Static vs Kinetic Friction in Physics Problems?

Thread starter Coldchillin
Start date Feb 19, 2007

AI Thread Summary

To determine whether to use static or kinetic friction in physics problems, assess if the surfaces are slipping or not. If the surfaces are in motion relative to each other, kinetic friction applies; if they remain in contact without slipping, static friction is relevant. Begin by analyzing the conditions to see if the block can remain stationary on the slab. Understanding these distinctions is crucial for solving friction-related problems accurately. Proper identification of friction type is essential for correct calculations in physics.

Feb 19, 2007

Coldchillin

http://img175.imageshack.us/img175/2448/picture1wt8.png

I am having trouble deciding when to use the static and kinetic frictions and what to do about this problem. Thanks for any help!

Last edited by a moderator: May 2, 2017

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Feb 19, 2007

Doc Al

Mentor

If the surfaces slip, then you have kinetic friction; if they don't, it's static friction.

Start by figuring out if it's possible for the block to not slip on the slab.

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