Bird's Journey From Train To Train

Suppose distance between SECUNDERABAD & CST is 1000 KM. Railway tracks are in straight lines with no curves in between.

A train with uniform speed of 100 kmph departs from CST at 9:00 AM. Same day on same track other train from SECUNDERABAD departs at 10:00 AM with uniform speed of 80 kmph.

A bird sitting on engine of train that departed from CST starts traveling toward the SECUNDERABAD & after touching the engine of that train travels back to CST train. A bird repeats this until trains collide.

How much distance the bird traveled & how many times did it travel to & fro? 

Click for the answer! 

Distance Traveled By The Bird

Here is the question! 

Let's divide answer in 2 parts.

1.Finding distance traveled by the bird.

The SECUNDERABAD train is one hour late till then CST train covers 100 km.

Hence effective distance is 900 km

Total speed of approach = 100 + 80 kmph

Total distance covered = 900 km

Time passed before trains collide = 900/180 = 5 Hours

Speed of bird = 120 kmph

Distance covered in 5 hours by bird = 120 * 5 = 600 km

Distance covered in first hour by bird = 120 km

Total distance = 600 + 120 = 720 km



2. Finding how many times bird traveled back & forth.


1st travel -

Total speed of approach = 120 + 80 = 200 kmph

Total distance to be covered = 900 km

Time required to meet each other = 900/200 = 4.5 Hours.
 
2nd travel -

Distance traveled by CST train in 4.5 hours = 100 x 4.5 = 450km

Distance traveled by SECUNDERABAD train in 4.5 hours = 80 x 4.5 = 360 km

Distance between 2 trains = 900 - (450+360) = 90 km

Time left for collision is 5 - 4.5 = 0.5 hrs.


So bird ends up with 1 complete round.

How To Reach The Island?

Abhijeet wants to reach an island which is in the middle of the river. The island is 30 feet from the edge of the river. As shown in the picture below he got two wooden planks about 29 feet each.

          How to reach there?

How can Abhijeet reach the island? 

1. This is how he reached!

Source 
 

Trick To Reach The Island.

Here is the task! 

A picture is worth thousands of words.

  Finally, reached there!

The Honest and Dishonest Guards

You’re in a room with two doors. There’s a guard at each door. One door is the exit, but behind the other door is something that will kill you. You’re told that one guard always tells the truth and the other guard always lies. You don’t know which guard is which. You are allowed to ask one question to either of the guards to determine which door is the exit. 

What question should you ask?

Exit door

Here is that question! 

Source 

Question to Find The Exit Door

What was the situation? 

What if I tell you that you have to ask only one question to anyone & choose the opposite door? Yes, be patient & read further.

Ask anybody this question.

"What would other guard answer if I ask him which one is exit door?"

Now there are two possibilities.

1. If the guard is truth telling then he knows other guard would lie & point the door leading towards the death. So he will point that door.

2. If the guard is lying then he knows other truth telling guard would have pointed right door.But in order to lie, he would point to opposite door! 

Six Glasses in a Row

There are six glasses in a row. The first three are full of orange juice, and the next three are empty. By moving only one glass how can you make them alternate between full and empty?

Make it alternate!

Here is solution!

Alternate Glasses in a Row

What was the riddle? 

All you need to do is pour 2nd glass into 5th one! It is as simple as that

one! See Below!

To make it alternate!

On a Mission of Fishing

Two fathers and their two sons go fishing together. They each catch one fish to take home with them. They do not lose any fish, and yet when they arrive at home they only have three fishes. 

How can this be?

This is how it can be! 

Source 

Three Generation On Mission

What's the matter? 

There are grandfather, father & grandson. So there are 2 fathers viz. father & grandfather while there are 2 sons viz. father & grandson! Three generations on the mission.

Three Generations

Which Coin is Counterfeit?

You are given eight coins and told that one of them is counterfeit. The counterfeit one is slightly heavier than the other seven. Otherwise, the coins look identical. Using a simple balance scale, how can you determine which coin is counterfeit using the scale only twice?

Identify The Fake Coin

  
This is how it can be found! 

Source 

To Identify The Counterfiet Coin!

Why it was asked to? 

1. Make a group of 3 coins each. Weigh these groups against each other.

2. If both groups weigh equal then weigh remaining 2 against each other. Heavier coin would be easily identified.

3. If one of group is heavier, then take out coins of this group.The counterfeit coin is among them.

4. Now weigh 2 of 3 coins of this group against each other.

5. If both are equal then obviously third one is counterfeit.

6. If one of them is heavier then obviously that one is counterfeit. 

 

The Safest Room - Lateral Thinking

A murderer is condemned to death. He has to choose between three rooms. The first is full of raging fires, the second is full of assassins with loaded guns, and the third is full of lions that haven't eaten in 3 years.

Which room is safest for him?

The Safest Room

Which one;find it here! 

Source 

The Safest Room - Lateral Thought

What was the puzzle?

If murderer has a little brain then he would choose the third room 

straightaway. How lions can stay alive for 3 years without eating anything? 

"He is my son"

A man and his son are in a terrible accident and are rushed to the hospital in critical care. The doctor looks at the boy and exclaims "I can't operate on this boy, he's my son!"

How could this be?



Here is that lateral thought! 

A Doctor Can Be Mother

Why it was required? 

The doctor is mother of that son!

Visual Illusions Psychology

Which monster looking bigger? The one which is chasing the other? Right?

Bigger Vs Smaller

Now look at this. What's your take now?

Equal Heights

Both are of same size. A 3D tunnel built around deceives your visual system & totally changes how it perceive things.

Now take a look at this. Are these straight lines or not? Definitely not! Right?

Straight or Curved

But you are totally wrong! Have a look at this.

Only Straight Lines

Again white & black checks surrounded in certain disorder changes how you perceive things.  

Checker Shadow illusion

Which square is darker here; A or B?

A is darker or B

The A appears darker than B here. But that's not the reality. Both shares equal levels of brightness & gray levels. A printer would you same ink to print those squares. 

Equally Darker

What's challenge to visual system here?

The task given to your visual system here is to determine the color of the object & here it is gray level. But shadow of cast plays here big role. The square under shadow reflecting less light than the one is not in shadow. Visual system need to do several tricks to compensate that shadow effect & determine the exact color of the square under shadow.

What tricks visual system uses?

1. Local contrast : Irrespective of shadow, a lighter check surrounded by more lighter checks is perceived as a check with more average lightness & vice versa. In the figure, the light check in shadow is surrounded by darker checks. Thus, even though the check is physically dark, it is light when compared to its neighbors. The dark checks outside the shadow, conversely, are surrounded by lighter checks, so they look dark by comparison.

2. Shadows often have soft edges while paints (here checks) have sharp edges. The visual system tends to ignore gradual changes in light level, so that it can determine the color of the surfaces without being misled by shadows. In this figure, the shadow looks like a shadow, both because it is fuzzy and because the shadow casting object is visible.

3. The "paintness" of the checks is aided by the form of the "X-junctions" formed by 4 abutting checks. This type of junction is usually a signal that all the edges should be interpreted as changes in surface color rather than in terms of shadows or lighting.
 
Conclusion :

The effect illustrates success rather than failure of our visual system. The illusion asking our visual system to act as a light meter; but it's definitely not built for it. What's the success of our visual system here is it breaks the information into meaningful components & then perceive different aspects of objects.



Courtesy : Wikipedia
 

Water Measurement With 2 Buckets - Puzzle

You have two buckets. One holds exactly five gallons and the other three gallons. How can you measure exactly four gallons of water into the five gallon bucket?

Assume you have an unlimited supply of water and that there are no measurement markings of any kind on the buckets.

How to measure 4 gallons?

Click here to know how it could be done? 

Source 

Water Measured Using 2 Buckets - Puzzle Cracked

What was the challenge? 

Method 1 :

1. Fill up the 3 gallons bucket & pour into 5 gallons bucket.

2. Again fill the gallon bucket & once again pour it into 5 gallons bucket. After completely filling 5 gallons bucket there will be 1 gallon left in 3 gallons bucket.

3. Empty 5 gallons bucket.

4. Pour that 1 gallon into 5 gallons bucket. Now fill up 3 gallons bucket. We have 4 gallons of water now 1 in 5 gallons bucket & 3 in 3 gallons bucket.


Method 2:

1. Fill up 5 gallons bucket & pour it into 3 gallons bucket. 2 gallons would remain in 5 gallons bucket.

2. Pour that 2 gallons of water into 3 gallons bucket. Now only space for 1 gallon left in 3 gallons bucket.

3. Again fill up 5 gallons bucket & pour into 3 gallons bucket containing 2 gallons of water left. So only 1 gallon can be poured & 4 gallons would be remaining in 5 gallons bucket.