Thursday, June 18, 2015

Why do hot baked products 'fall' if not given a resting period?

Most baked products have an infrastructure of starch (from flour) reinforced with egg proteins, and filled with fats and sugars and the most important - air. The starch portion of the flour gels and creates a web-like protein-gluten mesh. The carbon dioxide from the baking powder or baking soda will expand the cake. The protein-gluten mesh holds those bubbles in place.
These air bubbles need to set. If given proper resting time the whole protein network hardens and holds the bubbles in cakes. But when the gluten is hot, it's still very soft and can easily collapse is exposed to cold air. When you expose it to a sudden cold air, the bubbles contract, with the protein mesh not firm enough to hold. That’s why when you take a cake out early from an over, the cake can collapse because a structure hasn’t set yet. The simple answer as to why cakes collapse is the network of proteins and starches are not strong enough to hold the expansion of air.

Sunday, November 30, 2014

What is difference between values, morals and ethics?

Life is a universal, objective value. We might take this point for granted, but we all have the life value, or we would not be alive. Life is also a dual value – we value our own life and the lives of others.
Values have an intrinsic worth in usefulness or importance to the possessor. Values are the things people determine to be the most important in their lives. 
Morals are relative values that protect life and are respectful of the dual life value of self and others. Morals have a greater social element to values and tend to have a very broad acceptance. They are far more about good and bad than other values.
Ethics are moral values in action. Ethics tend to be codified into a formal system or set of rules which are explicitly adopted by a group of people. Ethics are thus internally defined and adopted, whilst morals tend to be externally imposed on other people.

To summarize, 'Values motivate, morals and ethics constrain'. In other words:

  •  Values are our fundamental beliefs, describes individual or personal standards of what is valuable or important 
  •  Morals are values which we attribute to a system of beliefs
  •  Ethics is about our actions and decisions

Wednesday, November 26, 2014

Why do we dream?

A dream can include any of the images, thoughts and emotions that are experienced during sleep. It is an involuntary activity. 
Despite improvements in medical technology and sleep research, experts today still have not reached a conclusion about why people dream. They have, however, developed some interesting theories.
Some experts believe dreams are a way to process all the events and emotions we experience throughout the day. They believe dreams play an important role in our physical, mental and emotional health. Similarly, other experts claim dreams are a form of problem-solving. They believe our dreams provide us with a safe place to work through problems, questions and dilemmas in our lives. Some researchers suggest that dreams serve no real purpose is a mere bodily function. On one side of the debate are those who think dreams are random images, and on the other are those who think there is deeper significance to what we see in our mind's eye. Some scientists believe dreams are the cortex's attempt to find meaning in the random signals that it receives during REM (Rapid Eye Movement) sleep.
Ranging from spiritual associations to a means of relieving stress, little conclusive research has been accomplished.

Monday, November 24, 2014

How does a sponge suck up water against gravity?

When a sponge is placed in a container full of water, it tends to suck up water, and get wet, even above the remaining water level. How does this water get sucked up against gravity?

This happens due to effect called capillarity, that causes water to move up narrow cylindrical channels. Capillary action is the ability of a liquid to flow in narrow spaces without the assistance of, and in opposition to, external forces like gravity. 

The pores of sponge are sufficiently narrow that the cohesion between water molecules and adhesion between the water and the surfaces of the pores combine to lift the water into the pores.Specifically the adhesion between the sponge fibers and the water molecules is high enough that water prefers to be touching the sponge more than other water molecules and so there is a tendency for it to "creep" up the sponge. In short, the capillary action, due to the pressure of cohesion and adhesion  causes the liquid to work against gravity.

Tuesday, July 8, 2014

Why do we see dust particles in bright narrow beam of light?


The particles are always present in air. Normally, they reflect less light, because the particles are very small. They can only be seen when a strong beam of light passes through the air. This is called Tyndall Effect. A very strong concentrated light beam reflects off of the dust in the air which can be seen in a darkened room, which is normally not seen.
Our eyes become more sensitive to light in dark rooms, especially if we give them a few minutes to adjust. Also the illuminated dust in a beam of light shows up because of the contrast between it and the dark background when the room is dark.

Wednesday, June 18, 2014

Why do dead bodies of animals/humans smell bad, while dead plants do not?

Decomposition of body begins at the moment of death, caused by two factors: autolysis, the breaking down of tissues by the body's own internal chemicals and enzymes, and putrefaction, the breakdown of tissues by bacteria. These processes release gases that are the chief source of the unmistakably putrid odor of decaying animal tissue.Decomposition of plant matter occurs in many stages. It begins with leaching by water; the most easily lost and soluble carbon compounds are liberated in this process. Another early process is physical breakup or fragmentation of the plant material into smaller bits which have greater surface area for microbial colonization and attack. 

During decomposition of animal carcass various chemicals such as ammonia, cadaverine, hydrogen sulfide, and putrescine are produced by the consumption of proteins by anerobic organisms which are characterized by their foul smell. However in the case of plants, due to a low protein content the extent of production of these foul smelling gases are very small. Therefore decomposition of plants are usually oudourless. Moreover the plants are primarily composed of cellulose and lignin, which are acted upon by very few microorganisms, which ultimately results in much delay in decomposition of the plant.