Consider the discrete signal x(n) = V3 cos (5πn)
Specify the condition which must satisfy for the signal x(n) to be periodic, and if applicable, give the period of the signal.

Aquick transition of the operating speed of a shaft from its critical speed will whirl amplitude. (a) increase (b) limit (c) not affect (d) zero

Ahelical coil spring has a mean diameter of 50 mm, a wire diameter of 5.5 mm and is wound with a pitch of 10 mm. the spring steel has an ultimate strength of 1250 mpa. find the force needed to compress the spring solid and the wire stress in this condition. state whether the spring will return to its initial length.

What is the fuid acceleration in vector form for the following velocity field? note i, j, and k are unit vectors. show all of your work.