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Using Physics: Rifling and Ballistics
Energy transfers from bullet to object on impact.
the gun the bullet goes, the slower it travels—it slows from friction with the
air. These factors are useful for a forensic expert trying to determine from
where a bullet was fired. The direction of bullet travel is usually not hard
for a forensic expert to establish. In much the same way a point of origin
can be determined for blood spatter, a bullet path can often be established
by examining the points of entry and exit and drawing a straight line back
along the suspected path of travel.
Bullet energy is the amount of energy transferred from the bullet to the
victim on impact. It is a useful figure because a ballistics expert can some-
times use it to determine how far the bullet traveled before it hit the target.
The amount of bullet energy decreases with increasing distance from the
