Mining Geology, Mine Development and Surveying · Mine Development · 1 mark · Numerical answer
An explosive’s detonation velocity is10500 m/s. In the shown D’Autriche test the fuse velocity is7000 m/s and the sampling separation is1 m. Find collision-mark displacement L from the fuse midpoint, in m to two decimals.
The transit-time difference between the two sampling points is1/10500 s. The opposing fuse fronts shift their meeting point from the midpoint by half the corresponding fuse-travel distance: L=7000×1/(2×10500)=1/3 m. Thus0.33 m.
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