#11 - Good Science Riddle
Many have heard it, but nobody has ever seen it, and it will not speak back until spoken to. What is it?
An Echo
#12 - Science Murder Riddle
A man was going to bleach his socks because they had gotten muddy the day before. As he was pouring the bleach into the washing machine, he spilled some on the floor. He got some cleaning fluid and mopped it up with a rag. Minutes later he was dead. What killed him?
When you mix bleach and ammonia [found in most cleaning products] it creates a deadly gas that can kill.
#13 - Popular Science Riddle
If you drop a 15 kg iron bar and a 5 kg bag of cotton from a height of 50 meters which will reach the ground first?
Both will reach the ground at the same time since acceleration due to gravity is a constant for all objects on earth.
#14 - Logical Maths Science Riddle
When Manish was three years old he hammered a nail into his favorite tree to mark his height. Six years later at age nine, Manish returned to see how much higher the nail was. If the tree grew by five centimeters each year, how much higher would the nail be?
The nail would be at the same height since trees grow at their tops.
#16 - Logic Physics Riddle
Imagine that you have a box which have two cogwheels – one big with 24 teeth and one small with 8 teeth. The big one is firmly attached to the center of the box which means it does not turn or move while the small one rotates around the big one.
How many times do you think that the smaller wheel will turn compared to the box when it turns once around the big one?
Three times is the most common answer however that is incorrect.
The small cogwheel will turn around four times.
You might already have deciphered that while turning against each other, the small wheel will turn three times (3*8) as the big wheel turns once (24 teeth). Now what we require is the big wheel to stop and the small one to turn around the big one. In this process, the small one will make another full turn on the way around the big one. Thus in total, it will make four turns.
#17 - Short Geography Riddle
Do you know of a place where the wind blows south and then suddenly shifts direction towards the north ?
The place is the South Pole. Until the point the wind reaches the pole, it is going south but the moment it passes the pole, it is going north.
#18 - Puzzles In Science
You are confined in a room and given two metal rods. Out of these two rods, one is magnet and the other is the iron rod. They look starkly similar. You dont have any other metal object in the room.
How will you decide which one of those is magnet?
This is pretty simple as the magnet has its magnetic field at poles in general. Then you can just keep one rod on the surface and bring the tip of the other rod towards the center. If the rod which is lying down gets attracted towards your rod, then the one you are holding is the magnet and if it does not then the one lying down is the magnet.
#19 - Physics Riddle
Suppose that you are trapped on the surface of a frozen lake. The surface is so smooth and ideal that there is no friction at all. You cant make any grip on the ice and no wind is blowing to help you out. You have just a mobile phone with you which has got no reception disabling you to call for help.
How will you plan your escape before you freeze to death on the frozen lake?
You have been told that the floor is ideally frictionless. Thus, all you need to do is throw your mobile phone in the opposite direction and the throw will propel you in the other direction. Since there is no friction, you will be able to glide smoothly to one side even with as little kick as this. This is same as firing a gun.
#20 - Science Logic Puzzle
You have an empty wine bottle (too bad eh?) with a cork that has been secured at the top in a normal way. There is a metal ring inside the bottle that is suspended by a string.
How can you make the metal ring drop to the bottom if you are not allowed to touch anything - not the bottle, not the cork, not the thread and not the ring?
You just need a magnifying glass to do considering you are out in open with bright sun rays available to you. With the glass, you can burn through the string and thus making the ring drop to the bottom.