# Search results

1. ### Old battery charger

no it may damage the cells as they require a constant current supply chris
2. ### Solve by means of Laplace transforms

1. Please see attachment for Question I've put it into microsoft eqn editor. 2. I have not got a clue where to begin i don't want anyone to do it for me but some information on how i can do it for myself would be appreciated. 3. as above
3. ### Torque and Shear stress this time

Useful formula J = (pi/32)*(D^4-d^4) T/J = Sheer Stress/r T = Torque r = Radius of external diameter D = External diameter d = Internal diameter These are some formula I've tried working through but i need J or D to work it through.
4. ### Torque and Shear stress this time

I'm :confused: I'm OK at electrical theory but mechanical just doesn't compute. I have the following question if anyone can help. Determine the external diameter of a tube needed to transmit a torque of 30KNm if it has an external diameter twice that of its internal diameter. The sheer...
5. ### Mechanical Engineering Streeses

Mechanical Engineering Stresses I am really struggling with the following problem: A rectangular tube with no given length has the dimensions shown in the diagram (within the attachment). Find the maximum tensile and compressive stresses that such a section will experience due to a bending...
6. ### Compound angles

Thankyou Hallsofivy I did think i should be using trig identities . I was a little confused:confused: because the question was taken directly from a book it is written exactly as i wrote it in my request. P.S sorry about my grammer as i was rushing before work. Thanks again Chris...
7. ### Compound angles

i am just about to start an electrical course at college and I've been reading up on some mathematics i will need when i start my problem is i don't know much about compound angles and trig and i want to complete some examples within a book the following problem is the one i need help with...