I'm an electrical engineer who has a passion for math and physics. I love helping others learn, and I am using this platform to reach other students, that I may not be able to reach via traditional tutoring services.
Yeah there's a U.S. exam and the International Exam. The international exam is tougher overall, but the scoring is more generous (lower threshold to get a 5 for example). And they never release the international exam FRQs unfortunately.
Yes I agree this is a problem. The biggest problem I see in physics education is that instructors wait for students to be wrong about a physics problem in class then correct them. This means students have to first think through the problem, arrive at the wrong answer, then correct their minds in the middle of class. Instead, if the instructor demonstrated the correct way to think about the problem from the start, correction would not be necessary. - I think physics instructors are attempting to increase critical thinking skills, but this is an excuse for the fact that physics content is not complicated and can be learned in about 30 min or less during a typical class period
For the slope question part, I did T on the y axis and (square root)M on the x axis. Is that ok? Or would I only recieve points for doing T^2 and M for the variables.
Hello Mr Tsao, I got my AP scores from my university status page and got a 5 on AP Physics C: Mech, and I wanted to thank you for that! Your videos with past free responses, and occasional videos for physics c, helped me get my 5. Thanks again!
Welp. This is gonna be good for me doing Physics II and E&M this fall but bad for me who wrote Mechanics last month. Collegeboard better lower the 5 threshold for this years exams to compensate for our mental health
Hey, Allen! Love the updates and reviews. My school had a power outage when the AP Physics 1 Test was given out so that test was canceled and my class was given another test instead. If you know what test form was given to students like me could you please review the questions for us?
Unfortunately those questions are not released so I can't make a video for them. Sorry I know the test was probably very different but I hope it turns out well!
Grade isn't really much of a prerequisite. The key part is you feel comfortable with algebra and are taking Precalculus concurrently (there's a few topics from precalculus you need for the later units in physics)
I thought the ap physics 1 changes made the class slightly harder, given the new unit on fluids meant less time to cover the other important topics. But I agree the changes seems like a net positive overall
I think one of the hardest things in mechanics is deciding whether to use forces, energy, or momentum in the analysis. For beginner students, I think that can be really challenging. So adding in new topics like fluids makes the mechanics portion weigh less because there will be some fluid material that you will never confuse for other mechanics topics. Even though it's more to cover, it makes the exam easier overall.
First. By the way, these changes make me more interested in ap physics 1, which I am taking next year. Ap physics 2 seems interesting too with new subtopics.
I've heard the late tests are very hard. I do think the curving is more generous on them though (don't know for certain but harder tests are usually curved more generously). You did your best and just have to wait and see how it turns out.
How do we know that there is a normal force for (c)i? How do we know it is going faster than the threshold to push it into the ramp? I believe at point c it could just have G acceleration and still stay in contact with Edit: the speed at that point is sqrt(4r) and the minimum speed is sqrt(10r) so the scenario is already impossible anyway
It's not impossible. The minimum speed it needs is sqrt(gR), and the speed at that point is sqrt(4gR) which is greater than sqrt(gR). I think you mistaken the speed by dropping your g (10) at some point.
@@AllenTsaoSTEMCoach Yes, I did forget that. I was doing it mentally. Thanks for the correction. Anyway, would there be a case that normal force is not included in the FBD but the block stays in contact?
@@asherwiggin6456 if it's in contact, there's always some normal force (otherwise it wouldn't be in contact). If the contact was very very weak, then the normal force could ALMOST be 0. But if there's any contact, there's a normal force.
Shouldnt tension force and pivot force be drawn at the same angle? We could calculate later that tension exerts a force upwards that is half the beam’s weight. The other force keeping the beam in vertical translational equilibrium is the upward pivot force, which should also exert a force that is half the beams weight. Also, to keep the beam in translational equlibrium, the magnitude of the horizontal component of the pivot’s force is the same as the magnitude of the horizontal component of the tension force. From this, we can deduce that the ratios of the forces’ respective components are the same. Therefore, the angles will be the same.
Yeah that's true but they would not make you do that when asking to draw a FBD. You are only needed to have a general shape and not as detailed of a FBD as that.
Can i say that work was smallee due to a smaller gravitational force but the same vertical displacement? I put that as part of my answer for part a. I still included larger radius leading to snaller g. Will i lose points?
@@AllenTsaoSTEMCoach yep, but they do make them relatively similar to each other, so if you were to, oh I don’t know, watch all the sections video frq’s youd probably have a pretty good chance at figuring out the one for the makeup
Where is the axle force in frq 3 coming from if there is negligible friction between the axle and the disc Why is it assumed that this system is at rest, why does there have to be a force to counteract tension and gravity
It's coming from the surface of the axle. Just because there's no friction does not mean there's no normal force. A block can slide down a frictionless ramp and have no friction but still have a normal force. Why must there be a normal force? Because we do have to assume the rod is not accelerating to the left. It's a fixed axle and it wouldn't make sense for the rod to accelerate to the left, which is what would happen if there were no other horizontal force. I agree the assumption of rotational torque being 0 is a bit of an assumption as they didn't state explicitly that it's not rotating. But it wouldn't really be solvable otherwise. I don't think it's reasonable to assume the rod can just swing left freely though.
