Recent content by Eeduh

That is not correct. Any force will ultimately be split in the part that acts along the radius (axis of rotation to point of force), the translation, and perpendicular to this radius, which when multiplied by the radius creates the torque. If the resultant force is 0, there will neither be...

Yes, or I could make it a bit easier so I can use my existing algorythm. If I detect the resultant force is 0, I just take one force, and calculate the components acting on rotational and translational acceleration on the rigid body. Then I move the point the force acts on to twice the original...

Thanks, that clears something up. As for the clockwise/counter clockwise thing, the same would go for the x components then. The x component of force B causes a clockwise torque, while the x component of force C a counter clockwise one. I see that I accidentally calculated that the right way...

Ok, I think I was basically doing what you said, but in a way too complicated way. If I hadn't rounded down to 4 significant numbers I think results would've been the same. Indeed, by 'at 30,40' I meant x,y coordinates. And the green lines are the torque arms so to say, at which the torques are...

Ok thanks again. I've tried to use your method with an example. Just made up a random body with random forces and numbers to test it. Now, I think by what you told me I did it correctly up to point 4. I end up with 2 numbers, 1 for the x devision and one for the y devision, but what to do now...

Thank you very much for your reaction, think I get the idea, just have a few questions to be sure. By 'the summed torque value', I take it you mean splitting each torque into it's x and y components, and adding those components up. In my view it would make little sense summing torques up...

Hi, I'm attempting to do a simulation of rigid bodies dynamics, and have ran into a problem. Homework Statement It can and at some point will occur that multiple forces will be acting on a rigid body, at different points with different strength and under different angles. Obviously...

Allright thanks, I think this will help. btw, I don't have a book :P I want to know this for myself, doing some programming. But I'll have a look on the internet again, and I'll figure it out.

Sorry not really.. I'm not very familiar with integration. Would you be so kind of giving me an example for this problem? For example, with the axis of rotation at 7,2 when the vertexes of the triangle are at 0,0; 17.32,10; 20,0? I understand if this would be too much to ask.

Homework Statement I want to calculate the moment of inertia of a 2d triangle. Let's say we've got a triangle with sides of 20 units. So it has width 20 and height 17,32. Also, let's say this triangle has a mass of 173.20 mass units (just used the surface). Now I want to calculate the...

Yeah I get it now but there remains a problem. For a rigid body, you theoretically have to sum up all the point moments of inertia. But how am I going to approach this then? For a 2d rigid body in a game, this would mean dividing the mass by the amount of pixels the object is built from...

Hmm I still don't really get it.. perhaps I should read some more on the subject. Thanks anyway.

Allright thanks, that's at least one step in the right direction. But the distance from the axis of rotation to what? CM? Because there's a problem with that which I've allready described in my first post..

Hi, I'm trying to teach myself some physics (dynamics in this case) and there's something I don't really get. It's how to calculate the moment of inertia. I know the standard formula is I = m*r^2 for point masses, and I = (1/3)*m*r^2 for rigid bodies with equally divided mass, which is the...