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Assess your understanding of Mechanical Shock Testing
  1. The most appropriate "classical" pulse shape to describe impacts with or retardations by, a linear rate system, e.g. Impacts involving resilient structures is:
    (a) Half sine   (b) Final peak sawtooth  (c) Trapezoidal   (d) Initial peak sawtooth  (e) Rectangular   (f) Triangular.


  2. What characteristic of compression design accelerometers makes them unsuitable for shock measurements?
    (a) High output sensitivity   (b) Base strain sensitivity   (c) Non-linearity   (d) Phase shift   (d) Frequency response


  3. The advantage of a terminal peak sawtooth test pulse is that:
    (a) it is easily generated using an electromagnetic shaker   (b) it transmits most energy into the test structure      (c) there are no nulls in its shock spectrum response    (d) it has a large residual component


  4. Excitation of a fixture's resonant frequencies during shock testing can have an effect on the attached test item as follows:
    (a) the item may be over tested   (b) the item may be under tested   (c) there will be no effect on the test item.


  5. The figure below illustrates the initial Shock Response Spectrum obtained from which of the following "classical" shock pulses prescribed in many specifications:
    (a) Trapezoidal    (b) Half sine    (c) Final peak sawtooth.

  6. Calculate the shock load in Newtons for a critical component of mass 2kg and natural frequency 200Hz which is exposed to the shock response spectrum shown below.