Passage Based Questions[Forensic Science]

Read the passage carefully and answer the following questions(Q1-Q5):-

By 1900, Clarence Dally was suffering radiation damage to his hands and face sufficient to require time off work. Due to him being right handed, he used his left to test the beam from the machine. This caused his left hand to be affected before his right^. In 1902, one lesion on his left wrist was treated unsuccessfully with multiple skin grafts and eventually his left hand was amputated. Ulceration on his right hand necessitated the amputation of four fingers.

These procedures failed to halt the progression of his carcinoma, and despite the amputation of his arms at the elbow and shoulder, he died from mediastinal cancer. Dally is thought to be the first American to die from the effects of experimentation with radiation.

1. What is radiograph?

1. Film exposed by X-Rays
2. Film exposed by IR rays
3. Film exposed by UV rays
4. Film exposed by gamma rays
5. All of these

Answer-1

Explanation

• X-Rays:- used to examine objects that are invisible to naked eyes. It possess very small wavelength. For quick inspection of an object under x-rays, a fluoroscope is used which contains a calcium tungstate fluorescent screen.
• IR rays:-Fall in spectral region of longer wavelengths immediately below visible range. They are readily absorbed & converted into heat energy. It has no fluorescent effects. Its source is 1000watt tungsten filament lamp. Red filters are used to filter out visible light & permit only IR rays. Mostly used by questioned document examiner. Applications:- obliterated writing, ink examination, erasures, charred documents, paints, GSR etc.
• UV rays:-when apply on any object, fluorescence occurs due to substances have the power to receive radiant energy of a certain wavelength & to convert portions of that energy into higher wavelength within visible range, results invisible glow. Convenient source is quartz mercury vapour lamp. Applications:- alteration in documents, paper examination, secret writing, sealing wax, teeth, glass, fingerprints, stains, laundry marks, gems etc. 

2. Which among the following is not the example of application of hard X-rays?

1. Identification of dead bodies
2. Suspicious packages
3. Counterfeit coins
4. Jewellery examination
5. All of these

Answer-4

Explanation

Application of hard X-rays:-

1.       Identification of dead bodies

2.       Suspicious packages

3.       Counterfeit coins

4.       Contraband

5.       Gunshot wounds

6.       Glass

7.       Fingerprints

8.       Gems

9.       Soil

10.   Structural defects

Application of soft X-rays:-

1.       Jewellery examination

2.       Paintings

3.       Gunshot wounds

4.       Secret & obliterated writing

5.       Paper examination  

3. Longer wavelength (4-25kv range) have less penetrating power are called-

1. IR rays
2. soft X-rays
3. UV rays
4. hard X-rays

Answer-2

Explanation

• Longer wavelength (4-25kv range) have less penetrating power are called soft X-rays
• Short wavelength (50-140kv range) have more penetrating power are called hard X-rays 

4. An IED concealed in a suitcase can be best detected by-

1. Gamma rays
2. soft X-rays
3. UV rays
4. hard X-rays 

Answer-2  

5. A person who are involved in smuggling & are transporting smuggled gold (kept it in a briefcase) which among the following rays are used to detect it?

1. Gamma rays
2. Hard X-rays
3. UV rays
4. Soft X-rays
5. IR rays

Answer-2