HOW NOT TO SLIP AND FALL IN BATHROOM

We mainly talk about electric, magnetic, gravitational and nuclear forces. But the frictional force also plays important role in our daily life.
How the frictional force arises? When one body moves over another body, a opposing force called friction arises. When liquid flows, it flows in layers and here the frictional force is called viscous force. Irregularities in the contacting surfaces, adhesive force between the surfaces and gravity also contribute to the frictional force. Friction is responsible for everyday activities like eating, drinking, writing, walking etc. Without friction "there will be many slips between the cup and the lip"

MEASURE OF FRICTION

'Co-efficient of friction" is used to measure the friction. It is the ratio between the force which is just enough to move the body' and the weight of the body (in simple terms). It normally falls between 0 and 1. The bathroom tiles should have this value from 0.4 to 0.7. Higher the value, more safe we are.
Gravity facilitate friction. Because the gravity brings objects together. In space, no gravity hence no friction.
Friction creates heat. That is why match box works. In the microwave oven, microwave agitate water molecules in the food and friction arises and warms up the food.
Rail road reduces the friction greatly. Hence the train is able to carry lot of people and load with less energy. But still, the ticket is costly because of overhead charges and maintenance.
All the automobiles and machines require oil and ball-bearings to reduce friction. Without oil, they will consume lot of energy and wear out quickly.
Hence, the friction is "the necessary evil" . Give the devil its due.
---------------------------------------------------------------------------------------------

Comments

THE EARTH, A SUPER ORGANISM

JOIN MY COURSE: "Become a programmer in a day with python" A man called 'love lock' (what a name) proposed a theory called Gaia theory, named after Greek Goddess. It says, "Earth is a self-regulating organism like a human being. The organic life in it interacts with in-organic matter and maintains atmosphere, temperature and environment". Hence the earth is still suitable for the life to thrive. Imagine, in a particular place, there are lot of flowers. Some flowers are white and some are darkly coloured. We know, white reflects light and heat while dark absorbs the same. White flowers can thrive in hot climate. But dark flowers requires cold climate. The absorption and reflection balances and the environment reaches average, warm temperature at which both the flowers can co-exist. This is the essence of "Gaia" theory. On our earth, the oxygen constitute 20% of the atmosphere. The oxygen level is always mai

THE PARABOLA

A jet of water shooting from a hose pipe will follow a parabolic path. What is the so special about parabola. Y= x^2 Draw a graph for the above equation. It will result in a parabola. This parabola is also called unit parabola. Any equation involving square will yield a parabola. Example: Y = 2x^2 +3x+3 (also called quadratic equation) X= 2 and -2, both satisfies the equation 4 = X^2. Parabolic equations always have two solutions. Any motion taking place freely under gravity follows parabolic path. Examples: An object dropped from a moving train, A bomb dropped from flying plane, A ball kicked upwards. If a beam of light rays fall on the parabolic shaped mirror, they will be reflected and brought to focus on a point. This fact is made use of in Dish Antenna, Telescope mirrors, etc. Inverted parabola shape is used in the construction of buildings and bridges. Because the shape is able to bear more weight. A plane

DISORDER IS THE "ORDER OF THE DAY"

Imagine a balloon full of air. The air molecules are moving randomly inside the balloon. Let us pierce the balloon with a pin. The air rushes out. Why should not the air molecules stay inside the balloon safely and ignore the little hole? That is not the way the world works. The molecules always "want to occupy as many states as possible". Hence the air goes out in the open to occupy more volume. The things always goes into disorder (entropy) and the disorder increases with time. The above statement is what we call "second law of thermodynamics". Consider a cup of coffee on the table. Suppose the heat from entire room flows to your cup of coffee, the coffee will boil and the rest of the room will freeze. Freezing means bringing things to order and arrangement. It violates the second law. Hence it will never happen. Hence heat must flow from high temperature to low temperature and not the other way. The air molecules in y

sciencecapsules

Search This Blog