In a control system, an accelerometer consists of a 4.75-g object sliding on a c
ID: 1380624 • Letter: I
Question
In a control system, an accelerometer consists of a 4.75-g object sliding on a calibrated horizontal rail. A low-mass spring attaches the object to a flange at one end of the rail. Grease on the rail makes static friction negligible, but rapidly damps out vibrations of the sliding object. When subject to a steady acceleration of 0.736g, the object should be at a location0.465 cm away from its equilibrium position. Find the force constant of the spring required for the calibration to be correct.
__________ N/m
Explanation / Answer
Fs = Fa
k*x = m*a
k = m*a/x
Substituting the known values (m=0.00475 kg, a=0.736g =0.736*(9.81 m/s^2) =7.22 m/s^2, and x=0.00465 m) gives:
k = (0.00475 kg)*(7.22 m/s^2)/(0.00465 m)
k = 7.375 N/m