physics help 4
posted by kelsey .
An astronaut on a small planet wishes to measure the local value of g by timing pulses traveling down a wire which has a large mass suspended from it. Assume that the wire has a mass of 4.10 g and a length of 1.60 m and that a 3.00 kg mass is suspended from it. A pulse requires 64.3 ms to traverse the length of the wire. Calculate the local g from these data. (You may neglect the mass of the wire when calculating the tension in it.)
Get the wave speed from the ratio
(wire length)/64.3*10^-3 s
The wave speed equals the square root of (Wire tension)/(wire lineal density)
Solve for the wire tension, T. That will equal the weight (in Newtons) of the 3 kg mass, from which you can derive g on that planet.