Solving the Crime Scene Riddle: Can You?

In summary, the conversation revolved around a riddle involving a man who was shot and killed, with one bullet getting embedded in a heavy wooden chair. A suspect was caught with a gun that had a high velocity and long barrel length, leading to a discussion about whether or not the gun could have been used in the crime. The conversation then moved to a different riddle involving a man found stabbed to death with only a puddle of blood and water at the crime scene, and a detective claiming to be able to determine the murder weapon from that information alone. Other variations of the riddle were mentioned, including a person found hanged in a locked room with a pool of water underneath and a dead man and monkey in a room with strange
  • #1
fargoth
320
6
ok, the story goes like this:
a men was shot, one bullet killed him and the other missed him and got stuck into a heavy wooden chair (about 20Kg).
the bullet made it 4cm into the chair, and the chair was pushed 6cm away by the 5 grams bullet (there were dragging marks on the wooden floor from the chair).

a suspect was caught with a gun, it had a 350m/sec nozzle velocity, and a 26 barrel length.

can you tell if this gun could be the one used in the crime scene from all the information you gathered so far?
 
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  • #2
Sure... dig the slugs out and do a ballistics comparison. If you mean in the mathematical sense from the numbers that you posted, I don't think so. You'd need to know what weight of slug the gun uses to determine the muzzle energy and compare it to that used to move the chair. The barrel length is irrelevant.
 
  • #3
This is blatantly a homework question, which belongs in that subforum. You shouldn't misrepresent it otherwise.

What steps have you already taken - how much have you reasoned out so far?
 
  • #4
Only Gil Grissom could answer that, duh. :rolleyes:
 
  • #5
Rach3 said:
This is blatantly a homework question
Are you sure? He's a 3rd year undergrad. They wouldn't have something like that for homework, would they. :confused:
 
  • #6
Danger said:
Are you sure? He's a 3rd year undergrad. They wouldn't have something like that for homework, would they. :confused:

I'm not sure they wouldn't, the undergrad programs have for some time been sliding backwards (without friction).
 
  • #7
i know there are parts that are irrelevant - that's for making it harder...

and as for this being homework - it's not.
it's a riddle I've found, but i think it's broken - i too thought of energy camparisson, but it seems some important figures (such as the friction constant between the floor and the chair) are missing...
does anyone still have homework in this time of year? i thought everyone are having their exams now...

or that it's just a god riddle that i haven't managed to solve... that's why i posterd it here, to see if anyone does better then i.

oh, and by the way, two weeks from now i won't be undergrad anymore =)
 
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  • #8
Well danger gave you the answer to the riddle
 
  • #9
yeah, well, if danger solved it, then i solved it too before i posted it :biggrin:
i just think the one who wrote it had something else on his mind... (or maybe he just forgot to mention things, and it really was a VERY easy riddle...)
 
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  • #10
I've heard this one before. A single bullet killed the man and wounded another guy before falling undamaged to the floor. The bullet that imbedded itself in the chair was fired by a conspirator. The suspect was a patsy and the gun could never have fired the shots because there wasn't enough time.
 
  • #11
fargoth said:
it seems some important figures (such as the friction constant between the floor and the chair) are missing...
I first started to mention that one, but it occurred to me that you can work it out from the weight of the chair vs. the speed and weight of the bullet, and how far the chair moved.

fargoth said:
oh, and by the way, two weeks from now i won't be undergrad anymore =)
Congrats! :smile:
 
  • #12
Danger said:
I first started to mention that one, but it occurred to me that you can work it out from the weight of the chair vs. the speed and weight of the bullet, and how far the chair moved.
It's not as easy a calculation as it may appear. I spent a minute thinking about it and gave up. It'll take me much longer to figure out.

PS : This is essentially the objective of the problem - to determine the friction coefficient and see if it comes out to be some reasonable number. If not, the crime scene has been tampered with or set up.
 
  • #13
Here's a much less challenging one. A man was found stabbed to death. All that was found at the crime scene was the corpse, a puddle of blood, and a puddle of water. The detective claims that he can figure out the murder weapon from that information alone. What do you think it was?
 
  • #14
Obviously an icicle.................
Answer in grey.
 
  • #15
That's some nice sleuthing there.
 
  • #16
Tom Mattson said:
Here's a much less challenging one. A man was found stabbed to death. All that was found at the crime scene was the corpse, a puddle of blood, and a puddle of water. The detective claims that he can figure out the murder weapon from that information alone. What do you think it was?
A chihuahua.
It wet itself when it was stabbed into the man.
 
  • #17
Chihuauas pee water?? :confused:
 
  • #18
I think so.
 
  • #19
Thanks. It's my weird-weapons background. :biggrin:
 
  • #20
Here's a variation. A person is found hanged in a room locked from the inside and no other person in the room. There is no object in the room that the victim could have stood upon in order to get the hanging started. A pool of water is found under the victim.
 
  • #21
jimmysnyder said:
Here's a variation. A person is found hanged in a room locked from the inside and no other person in the room. There is no object in the room that the victim could have stood upon in order to get the hanging started. A pool of water is found under the victim.
That's an easy one, he was standing on a block of ice
 
  • #22
yomamma said:
That's an easy one, he was standing on a block of ice
Nope, it was a woman.
 
  • #23
you're just being mean
 
  • #24
An otherwise empty room, locked from the inside. On the floor is some broken glass, a puddle of water and a body. What went down here?
 
  • #25
Heart attack? Self-drowning? Not enough info.
 
  • #26
A dead man and a monkey are in a room. The man is holding a lighter, wearing a tutu, covered in baking soda and glued upside-down to the far wall. The monkey is spinning rapidly while playing a rendition of Mozart on his tuba. In the room are a puddle of water, 3 strands of blonde hair, blood on the ceiling, two pitchforks, a broken television full of cottage cheese, and a bowling ball with 7 finger holes. Using this information, what is the escape velocity for an electron from a pulsar in a chaotic orbit with two companion stars in a dark matter halo?
 
  • #27
Guillochon said:
A dead man and a monkey are in a room. The man is holding a lighter, wearing a tutu, covered in baking soda and glued upside-down to the far wall. The monkey is spinning rapidly while playing a rendition of Mozart on his tuba. In the room are a puddle of water, 3 strands of blonde hair, blood on the ceiling, two pitchforks, a broken television full of cottage cheese, and a bowling ball with 7 finger holes. Using this information, what is the escape velocity for an electron from a pulsar in a chaotic orbit with two companion stars in a dark matter halo?
Would that be an African electron or a European electron?
 
  • #28
DaveC426913 said:
Would that be an African electron or a European electron?

I don't know that!
 
  • #29
:rofl: :rofl: :rofl: :rofl: :rofl:
Guillochon and DaveC426913 - you got me laghing my a** off, i know this movie by heart.
 
  • #30
two shrubberies with a path in the middle so it has the two level effect is found dead under the mightiest tree in the forest, and a herring...
who killed the history teacher?
 
  • #31
If a chicken and a half can lay an egg and a half in a day and a half, then how long will it take for a cockroach to kick all the seeds out of a cucumber.
 
  • #32
Funny thread :rofl: :biggrin:
 
  • #33
Guillochon said:
A dead man and a monkey are in a room. The man is holding a lighter, wearing a tutu, covered in baking soda and glued upside-down to the far wall. The monkey is spinning rapidly while playing a rendition of Mozart on his tuba. In the room are a puddle of water, 3 strands of blonde hair, blood on the ceiling, two pitchforks, a broken television full of cottage cheese, and a bowling ball with 7 finger holes. Using this information, what is the escape velocity for an electron from a pulsar in a chaotic orbit with two companion stars in a dark matter halo?
42

Text added to satisfy a curious criterion.
 
  • #35
ForensicCrime said:
The pool of water and blood riddle is the oldest one in the book!
Well, it wasn't very old when the thread was posted... :biggrin:
 
<h2>1. How do you collect evidence at a crime scene?</h2><p>Collecting evidence at a crime scene involves a systematic approach, which includes documenting the scene, photographing and sketching the area, and collecting physical evidence such as fingerprints, DNA, and trace evidence. It is important to follow proper protocol and handle the evidence carefully to avoid contamination.</p><h2>2. What are the different types of evidence found at a crime scene?</h2><p>There are several types of evidence that can be found at a crime scene, including physical evidence (such as weapons, fingerprints, and DNA), documentary evidence (such as written documents or electronic records), and testimonial evidence (such as witness statements). Each type of evidence can provide valuable information in solving a crime.</p><h2>3. How do you analyze evidence in a crime scene?</h2><p>Analyzing evidence involves a combination of scientific techniques and deductive reasoning. Physical evidence can be analyzed using various methods, such as DNA testing, fingerprint analysis, and chemical analysis. Documentary evidence can be examined for authenticity and relevance. Testimonial evidence can be evaluated for credibility and consistency. Ultimately, all evidence must be carefully analyzed and interpreted to form a cohesive picture of what happened at the crime scene.</p><h2>4. What role does forensic science play in solving a crime?</h2><p>Forensic science is a crucial component in solving a crime. It involves the application of scientific techniques to analyze physical evidence and provide objective conclusions. Forensic scientists use their expertise in areas such as DNA analysis, ballistics, and toxicology to help determine the cause of a crime and identify potential suspects. Without forensic science, it would be much more difficult to solve crimes and bring perpetrators to justice.</p><h2>5. How do you ensure the integrity of evidence at a crime scene?</h2><p>Maintaining the integrity of evidence is crucial in solving a crime. This involves properly documenting, collecting, and storing all evidence in a secure and controlled environment. It is important to avoid contamination or tampering with the evidence, as this can compromise its reliability and admissibility in court. Following strict protocols and chain of custody procedures can help ensure the integrity of evidence throughout the investigation process.</p>

1. How do you collect evidence at a crime scene?

Collecting evidence at a crime scene involves a systematic approach, which includes documenting the scene, photographing and sketching the area, and collecting physical evidence such as fingerprints, DNA, and trace evidence. It is important to follow proper protocol and handle the evidence carefully to avoid contamination.

2. What are the different types of evidence found at a crime scene?

There are several types of evidence that can be found at a crime scene, including physical evidence (such as weapons, fingerprints, and DNA), documentary evidence (such as written documents or electronic records), and testimonial evidence (such as witness statements). Each type of evidence can provide valuable information in solving a crime.

3. How do you analyze evidence in a crime scene?

Analyzing evidence involves a combination of scientific techniques and deductive reasoning. Physical evidence can be analyzed using various methods, such as DNA testing, fingerprint analysis, and chemical analysis. Documentary evidence can be examined for authenticity and relevance. Testimonial evidence can be evaluated for credibility and consistency. Ultimately, all evidence must be carefully analyzed and interpreted to form a cohesive picture of what happened at the crime scene.

4. What role does forensic science play in solving a crime?

Forensic science is a crucial component in solving a crime. It involves the application of scientific techniques to analyze physical evidence and provide objective conclusions. Forensic scientists use their expertise in areas such as DNA analysis, ballistics, and toxicology to help determine the cause of a crime and identify potential suspects. Without forensic science, it would be much more difficult to solve crimes and bring perpetrators to justice.

5. How do you ensure the integrity of evidence at a crime scene?

Maintaining the integrity of evidence is crucial in solving a crime. This involves properly documenting, collecting, and storing all evidence in a secure and controlled environment. It is important to avoid contamination or tampering with the evidence, as this can compromise its reliability and admissibility in court. Following strict protocols and chain of custody procedures can help ensure the integrity of evidence throughout the investigation process.

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