This video covers the basic strategies and formulas you'll need to solve F=ma problems involving Ramps, which means you're looking at an angled surface or incline up or down which an object is sliding, crashing, or being pulled. If you're not sure about free body diagrams, definitely familiarize yourself with our free body diagram videos.
Acceleration of Box Down Frictionless Ramp (with Forces)
The problem in this video can be done without using F=ma, since we did just that back in the Frictionless Ramps Kinematics chapter. As you may recall, we said that for those problems, a=g*cosθ. Well, in this video we show how we got that result, which is a good way to get started on ramp force problems.
F=ma example: Dogs Pulling Dogsled Up Hill (no friction)
This video covers a fun problem where a pack of marginally tame wild dogs is pulling a sled up a snowy embankment.
Acceleration Of A Box Down A Ramp (with Friction)
In this ramp problem video, we finally add friction to the mix. But take heart: you'll still get to draw all those crazy components of gravity (the "mg triangle") on the free body diagram that I've tried to convince you to master.
Find Friction Coefficient (μs) Required To Prevent Box Sliding Down Ramp
This video covers one of those subtle ways that a professor can throw you off your game by asking for something different than they usually do in F=ma problems. In this particular example, rather than asking for acceleration, they ask for the coefficient of static friction μs!
How Long To Make A Runaway Truck Ramp (with friction)
This video covers a really cool real-world F=ma application involving ramps: those crazy ramps you'll see shooting off mountain highways, which are designed to stop runaway trucks (big trucks whose brakes have overheated and stopped working).
Crate Pulled Up Ramp By Horizontal Force (Difficult, with friction)
This problem might not seem so much worse than others we've seen in the ramp chapter, but it really is. Not only does it have friction, but the force we're solving for is not parallel to the ramp, so it has components in both the X and Y directions. You'll see what I'm talking about: lots of algebra in this one!
If you do not have an account, you should get one, because it is awesome! You can save a playlist for each test or each chapter, and save your "greatest hits" into a "watch right before the final" list (not that we recommend cramming, but when in Rome...)