At any crime scene, the two greatest challenges to the physical evidence are contamination and loss of continuity.
<h3>What is the meaning of physical evidence?</h3>
In evidence law, physical evidence (also called real evidence or material evidence) is any material object that plays some role in the matter that gave rise to the litigation, introduced as evidence in a judicial proceeding (such as a trial) to prove a fact in issue based on the object's physical characteristics.
The two types of evidence at crime scenes:
Biological evidence (e.g., blood, body fluids, hair and other tissues)
Latent print evidence (e.g., fingerprints, palm prints, footprints)
The biggest impediment to an investigation is the removal or loss of a piece of evidence from the scene of a crime.
Hence, at any crime scene, the two greatest challenges to the physical evidence are contamination and loss of continuity.
Learn more about the physical evidence here:
brainly.com/question/13505766
#SPJ1
<span>E=hc/wav. len
E = (6.62 x 10^-34 x 3 x 10^8)/0.0275 x 10^-9
E = 7.22182 x 10^-15 J
To convert to eV divide by 1.6 x 10^-19
E = 7.22182 x 10^-15/1.6 x 10^-19 eV
E =45.36 x 10^3 eV
Th energy, E, of a single x-ray photon in eV is = 45.36keV.
Number of photons, n = total energy/ energy of photon
n = 3.85 x 10^-6/7.22182 x 10^-15
n = 5.33 x 10^8 photons </span>
