Forensic Science and Physical Evidence Questions and Answers

Answer: D

CFSL Guwahati was started in 2011.

The Central Forensic Science Laboratory at Guwahati was set up by the Ministry of Home Affairs under the Directorate of Forensic Science Services to serve the north-eastern states. It was one of the newer CFSLs added to the older laboratories such as Hyderabad, Kolkata and Chandigarh.

1971, 1981 and 1991 are too early; Guwahati was not among the earliest central laboratories.

Answer: A

The correct match is a-iv, b-i, c-ii, d-iii.

These are the channels of a polygraph:

• Pneumograph: tubes around the chest and abdomen record respiration changes (iv).
• Sphygmograph (cardiosphygmograph): the cuff records blood pressure and pulse (i).
• Plethysmograph: records changes in blood volume in a finger, the pulse volume (ii).
• Galvanograph: records the galvanic skin response, the change in skin conductivity caused by sweating (iii).

Option B swaps the plethysmograph and galvanograph, and options C and D misplace the pneumograph, which records breathing, not blood pressure or pulse volume.

Answer: D

A scale is included to show the size of objects in the photo.

Forensic photographs of evidence such as wounds, footprints, fingerprints or tool marks are taken first without and then with a scale placed beside the object on the same plane. The scale allows the image to be printed at life size (1:1) and lets measurements be taken from the photograph for comparison.

Visual interest and composition are artistic concerns, not forensic ones, and the scale says nothing about time; the time is recorded in the photo log and the camera's metadata.

Answer: A

The criminal courts are (a), (b) and (c) only.

Section 6 of the Code of Criminal Procedure, 1973 lists the classes of criminal courts: Courts of Session, Judicial Magistrates of the first and second class, Metropolitan Magistrates and Executive Magistrates. Executive Magistrates exercise preventive and other powers under the Code, so their courts are criminal courts.

A Munsif court is the lowest civil court, dealing with civil suits of limited value, so any option that includes (d) is wrong.

Answer: D

The correct match is a-ii, b-i, c-iv, d-iii.

• Article 14: equality before law and equal protection of the laws (ii).
• Article 15: prohibition of discrimination on grounds of religion, race, caste, sex or place of birth (i).
• Article 16: equality of opportunity in matters of public employment (iv).
• Article 17: abolition of untouchability (iii).

These four, with Article 18 on the abolition of titles, make up the Right to Equality. The other options shuffle the same four rights and misplace at least two of them.

Answer: B

The laboratory was established in 1958.

Maharashtra's first forensic science laboratory was set up in Mumbai in 1958. It grew into the headquarters laboratory of the state's Directorate of Forensic Science Laboratories, and regional laboratories in other cities, such as Pune and Nagpur, were added later.

1952, 1962 and 1968 are not the founding year. The question is factual, and the other dates sit four to ten years either side of it.

Answer: D

This is surveillance photography.

Surveillance photography is the covert recording of people, places, vehicles and activities of interest to an investigation, usually from a distance with telephoto lenses and without the subject's knowledge. It documents meetings, movements and associations as evidence.

3D photography records objects in three dimensions for measurement and reconstruction, high-speed photography captures very fast events such as a bullet in flight, and aerial photography records scenes from above. None of these is defined by secrecy.

Answer: B

For greater depth of field you would shoot at F16.

The f-number is the focal length divided by the aperture diameter, so a larger f-number means a smaller aperture. A small aperture narrows the cone of light from each point, so objects in front of and behind the focus stay acceptably sharp, giving a greater depth of field. That is why evidence and crime scenes are photographed at small apertures such as f/16.

F2.8, F4 and F7.1 are wider apertures, giving progressively shallower depth of field; f/2.8 throws everything outside the plane of focus out of focus.

Answer: D

A tripod is used to add stability and reduce camera shake.

Forensic photographs must be sharp and accurate. Close-up photographs of fingerprints, tool marks or footwear impressions, and photographs taken with small apertures or long exposures in low light, need slow shutter speeds, and any hand movement would blur the image. A tripod also keeps the camera parallel to the evidence, which is needed for scale photographs.

Candid shots, deliberate motion blur and creative angles are artistic aims, the opposite of the steady, standardised records forensic photography needs.

Answer: A

Such a computer is called a zombie.

A botnet is a network of computers infected with malware and controlled remotely by an attacker, the bot herder, through command-and-control servers. Each infected machine, called a zombie or bot, obeys commands without its owner's knowledge, for example to send spam or take part in distributed denial-of-service attacks.

Serf, vassal and thrall are historical words for people in servitude, which fit the idea of a slave machine but are not the term used in computing.