I'm just gonna start with a brief introduction of myself. I'm an 18 year-old highschool student from Southern Finland, a country in Scandinavia, between Sweden and Russia.
Anyway, I'm on my last year in highschool and was actually about to graduate this spring, however I hadn't completed enough courses to do that, so I'm graduating next autumn. I want to graduate asap, so I selected some courses I hadn't completed already, and one of these courses is Physics 5, it's basicly about mechanics, motion etc. etc.
Now, I'm REALLY bad at physics and math in general , and in this course I haven't got a teacher, so I need to learn this stuff without help from the school, and if I get a 4 (our grades are from 4 to 10) in this course, I will have to do it all over again

So here comes the part where I need help, and I really need to understand how this works too, because I have 6 homework assignments that I need to figure out and complete, then April 3rd, which is in almost two weeks, I have to orally explain to the teacher how I completed these assignments, how they're calculated, why etc., and then of course there's the exam.

I would be REALLY grateful if some of you guys could help me out!

I'm going to be posting on a few other boards aswell

I'll start with the two first assignments, I see that they're really simple basic mechanics, but there's still something I don't understand about them (I had my last physics course like 3 years ago). You have permission to laugh, I'm a newbie and I don't really care about that anyway, so go ahead if you must





What I basicly understand from this is that the Second Law of Motion is in effect and some force of 350N is pushing the wagon forward while a force of 295N is decelerating the wagon. Then we also have gravity which is 9.81 and the mass 12kg. Oh, and the Third Law of Motion is also in effect, because gravity and then the mass of the wagon is pushing against the ground.

So basicly F = 55N, m = 12kg, g = 9.81

But then how do I calculate it, what's the formula? Am I missing some other variables?





Here Newton's Second Law of Motion is in effect again. There's two masses. m1 is accelerating while m2 is going upwards.
So basicly there's: m1 = 8kg, m2 = 6kg, g1 = 9.81, g2 = 9.81

I'm a bit confused here though. Again, how the heck do I calculate it, what's the formula? Am I missing something?



Cheers!

Hi there, welcome to the forum.
At the top of this section is a fine post entitled Mechanics - a review, in which most of the important concepts in Physics are described. If you read through it you may find some of the issues become clearer.
Essentially it is all about applying the right equation to a given situation. F=ma is a commonly required equation, and is used in your first problem. The 'net' force is 55N and the mass of the thing is 12kg. F=55N, m=12kg - a = F/m =4 and a bit. The units of acceleration are distance/time/time or ms-2. ©.
I have to go out now but will try and have a look at the second later. The principle is definitely covered in the sticky'd post.
Good luck.