Recent content by Kyon

Hello, The answer to the first question is much more simple than what Astronuc said. (He is not wrong at all though, but he uses big artillery for a really simple problem in my opinion :smile: ). The power dissipated in lifting a 2.0 kg ball vertically at 3.0m/s equals what? Here is my...

After a quick google search, I think I've found the answer: using + and - for current intensity is just a convention to indicate the direction of the current. Positive intensity if the current go in the same direction as you decided on your drawing, negative otherwise. Just a convention...

Well, I don't really know, but that's what happen when you invert the inputs of an amperemeter. So, it's either a device convention to tell you the current go the other way or intensity is really counted negatively. In fact, I don't really know neither, but I'm sure a guru is going to...

Well, don't think I'm being harsh with you ledhead, but you should read your courses and your book once again. I mean, this kind of exercice is a direct application of what you should have learned. At least, it is here, in France. Here is a good advice to help you solve almost all...

Yes, this is just an error in your units. I didn't pay attention as I thought you did the conversion, but Kamataat is right. Anyway, accelerating from 43 to 70 km/h in 8.1s is way slower than an acceleration of 3.3 m/s² (i didn't do the math though) I think just doing the right conversion...