Dynamics - Particle kinetics Normal Tangential example 1

Thermodynamics: drive.google.com/file/d/1bFzQ...
Mechanics of Materials: drive.google.com/file/d/1P-pc...
Statics: drive.google.com/file/d/1aYY5...
Dynamics: drive.google.com/file/d/1_JTk...

[@morolayomi]

For the normal force in the x dir could i have done Ncos betA?

[@engineeringdeciphered]

Yes! N cos beta would be the same as N sin theta. But then you’d be solving for beta so just remember to subtract from 90 to get theta.

[@morolayomi]

Thank you sir. I have a clarification, at 2:36 when you mentioned that IF there was to be a force of friction when a car is going slowly, the friction would prevent the car from sliding down the track and if it was speeding up, it would prevent the car from sliding off the track. Does this explanation apply to every single inclined friction problem?