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1. Some questions regarding EMC

The main subject of it is about cable shielding in electromagnetic compatibility. I've googling myself but nothing much info about it. I got some answers from german , after translate is something like this ( dotn know correct or not ): 1. reflection produces ripples 2. to against strong...
2. Some questions regarding EMC

thanks for the reply , I really need to know why lamda >> L .. pls help
3. Some questions regarding EMC

HI, I got some questions regarding Electromagnetic Compatibility: 1. When we measure transfer impedance for cable shielding , why we have assume that lamda >> L ? 2. What is the difference between trasnfer impedance & admittance? My friend told me that the impedance in purely...
4. Material to dissolve enamel paint

hi, I spray with my keyboard with Spray paint ( i think is enamel paint ) and now i am regret - so i need a solution to dissolve it but i can't remember the name , can anyone tell me ? thanks
5. Energy is conserved ?

energy is conserved ??? hi, just read about energy conservation but i am not so clear about it .for example : a particle moves in uniform oscillation electric field - does the energy conserved ? what is the criterion for conservation energy? thanks
6. Potential conserved quantities

So i am correct ?? angular momentum of z and energy are conserved ?
7. Potential conserved quantities

no i am not familiar to Langrage mechanics - will learn next 2 months
8. Potential conserved quantities

My thought : angular momentum of z component and the energy of the system is conserved ... Pls tell me if there are more quantities are conserved thanks
9. Potential conserved quantities

hi, if i have mass possess potential U(x)=-Gm1m2/(x^2+y^2+(kz)^2 )^1/2 , i said angular momentum of z is conserved but not angular momentum of x , y .. is it correct ? what else is conserved ? energy ?
10. Projection with coriolis force

hi, i read lots of book regarding fictitious force - coriolis and centrifugal forces, but i am not clear how to determine the direction of the force.. example. if we throw a ball vertical up , how we can know the deviation from the original position ( from book we know that if the ball...
11. Motion of spring mass with charge in magnetic field

ya, i dont know is right or wrong - dv/dt= qBv/m -kx but the spring's motion is in x y plane ( if z is magnetic field) - how can i decribe the force cause by spring ?
12. Motion of spring mass with charge in magnetic field

hi, got a difficult question to ask : we can easily find the motion of charge in magnetic field.But now if the charge is attached to a spring, how can we find the general motion ? is it like a gyroscope ? thanks
13. Are you in inertial frames?

Thanks for the reply -- i am clear now thanks
14. Centripedal & Centrifugal force

yes, centrifugal forces and coriolis forces are called Fictitious force..
15. Centripedal & Centrifugal force

hi, what is difference between Centripedal & Centrifugal ? One is in inertial frames and the other in rotating frames? one is 'true' force and the other is fictitious force? thanks
16. Are you in inertial frames?

but his question is : How to determine that your lab is in inertial frame or not ?
17. Are you in inertial frames?

Are you in inertial frames??? hi, today my friend ask me 2 simple questions, too shame i cannot answer him...so i post it here: is the classroom an inertial system ?? earth is rotating around the sun - so ...can still consider as inertial ? 2. If u working in laboratory to find so...
18. Vertical Projectile with air friction

i will consider both conditions .. if the initial velocity is not too high - then is propotional to v , if not ( high velocity ) then is proportional to v^2... i got a long a strange solution for max height...
19. Vertical Projectile with air friction

i had the same equation motion, but how we can find the max height ?
20. Vertical Projectile with air friction

hi, If we throw a ball vertical upward, we can easily find the maximum height if ignore the friction.. So if we switch on the friction, how can we find the max height ?
21. Kernel of differentiation and integration

i asking a question but u ask me back ???!!!
22. Kernel of differentiation and integration

nevermind - i think i konw the answer
23. Kernel of differentiation and integration

hi, i got a algebra question regarding kernel 1.what is the kernel of intergration operator: T(p)= p'(x)? 2. what is the kernel of differentiation operator : T(p) = integration of p(x) from -1 to 1 thanks
24. Use identities to Prove linearly idenpendent

that mean any set of vectors contain a 0 cannot be linearly independent ? not independent but linealy independent
25. Use identities to Prove linearly idenpendent

determine following setd of vectors in F(-infinitity, infinitiy) are linearly independent (using appropriate identities) 0, [cos (pi*x)]^3 , [sin 3*pi*x]^5 pls help !
26. MATLAB Determine the machine precision in Matlab

hi, how to determine the machine precision in matlab and estimate from this how many bits are used in the mantissa ??
27. 2 simple vector spaces question

( a 1 ) --- is this 2x2 matrix a vector space ? sorry for asking this coz this is abstract 1 b me
28. Linear (in)dependent vector sets

how i use the identity to solve that problem
29. Linear (in)dependent vector sets

are 6, 3*(sinx)^2 and 2*(cosx)^2 - linearly independent ? Can someone explain how to determine it ?
30. 2 simple vector spaces question

so you are saying that : the set of all positive real numbers with operations x+y =x*y and kx=x^2 are vector space?