Recent content by sseebbeekkk

Ok, it does. Thanks.

I think the only potential energy is due to the spring. If the spring lies the ground then mgh=0

If a spring is not stretched or compressed, then there is no elastic potential energy stored in it. However in this case at the beggining the spring was stretched 2 metres (4-2=2), hence 1/2*k*s1^2 At the end, the spring was stretched 5 meters (7-2=5), hence 1/2*k*s2^2 'W' stands for: work...

Thank you for help. Dr. Courtney - is this equation correct ?

Homework Statement [/B]Homework Equations [/B] (1) (pink) Is it vertical displacement ? * 4 - 2 (unstretched length of the spring) ? (2) (blue) What does it mean ? * I was thinking that maybe they used The Pythagorean theorem (62+42)=7,2 ≅ 7) but I'm not sure. Besides I don't understand...

That was very concise and clear. Thank you :-)

Ok, finally I understand it (hope so) I can choose I=1/12ml2 = in that case (17.10) 1/12*20*32=15 or I=1/3ml2 = (center at 1.5) 1/3*20*1,52=15 It works :biggrin:EDIT: but if that what I have just written is true, I have got the following question...

Ok I have realized that I don't understand it fully (I miss something basic probably) According to this example we should calculate the moment of inertia using formula I=1/12ml2+md2 So why did the author in 17.10 use simply [1/12ml2]*α Instead of [1/12ml2+md2]*α

Ok, thank you :)

1. Material 2. Questions: a) (pink) Why does the author use two different values of inertia for the same slender rod ? The Attempt at a Solution [/B] a) I could assume that 1/3 is holding it at the end and 1/12 is holding it in the center. But it's not interchangeable because if I chose 1/3...