Saturday 10 December 2016
making a clinometer
clinometer |
How to make a clinometer?
introduction:
Generally, we use to measure an angle with the help of a protractor. But, the protractor alone can't be used for measuring the height of building or a tree or a tower. By using a clinometer, one can measure the height of any building or height of a tower, or height of a tower. The clinometer is basically used by surveyors and engineers belongs to civil branch. The clinometer consists of a weight attached to a piece of string hangs from the sighting device. When the clinometer is tilted upward to view the top of the building, the string moves across a protractor like face and indicates the angle of inclination.
construction of a clinometer:
materials required: 1 protractor, a piece of thread, 1 nail of length about 2.5 cm (for weight),
working procedure: Make a tiny hole at the center of the base line on the protractor, pass the taken thread through the hole, tie one end of the thread with nail, and another end should tie a knot in one end. The angle shown by the nail is 90 degree when the protractor is held with its straight edge horizontal and upside. Now the clinometer is ready which can be used for measuring the height of a building or a tree.
How to find the heights?
step 1: Measure the distance from the place where you stand to the base of the building
step 2: To find the height of the building, You look along the top edge of the clinometer, focus to top of the building, allow the thread to move freely around the scale of the protractor.
step 3: The angle shown by the nail is equal to the angle which the building makes the horizon.
step 4: By using the formula, h=dtan(angle), by taking the value of the angle, and distance between you and the building, multiplying the tangent degree and distance, one can find the height of the building or a tower.
precautions:
1. take the angle properly.
2. distance should be measured accurately.
3. one can use a stand to fix the clinometer.
Wednesday 7 December 2016
A SENSOR TO IDENTIFY pH OF BLOOD
A TINY BLOOD pH SENSOR DEVELOPED BY INDIAN INSTITUTE OF TECHNOLOGY, KHARAGHPUR students
IIT Kharagpur researchers have successfully developed tiny device to measure the pH of blood. The device works by measuring the imedance. The device relies on venous blood sampling for pH measurement.
The pH of a solution is a measure of the percentage of hydrogen ions available in a solution. The solution is said to be acidic, if the pH will be less than 7. The device was able to detect the pH of the blood in 10 seconds.
SOURCE: THE HINDU
states of matter
We
use to observe that the matter will be in three states. They are solid
state, liquid state, and gaseous state. The state can be changed with
the effect of pressure and temperature. The temperature can be
increased by increasing heat energy. Heat energy is a different energy
from other types of energies since, the heat is transmitted from higher
temperature body to lower temperature body. Whereas, the temperature is
the intensity of the heat energy. For example, when we touch an
object, if we feel it is cold, the meaning is that the person who
touched the object, the heat energy is transmitted from him/her to the
object, then we feel very cool. When we gain certain heat energy, we
feel more hot. In this way, the heat energy is the energy which is
transferred only due to the differences in the temperatures or different
intensities of heat energy.
SOLID STATE OF THE MATTER
If
we observe, an ice cube, the water is in solid state. In any solid
state of a matter, the molecules or atoms are very close and we don't
observe any space between each atoms. There is no enough space between
the atoms, there is a strong attractive force present between them. No
other particle can place in between the atoms of the solid
substances.
Due to these properties, solids have a definite shape, definite volume, definite mass.
LIQUID STATE OF THE MATTER
Water
is an example for liquid state of the matter. Liquids do not have a
definite shape, but they posses definite volume. Liquid state can be
achieved by heating a solid state of the matter. As we are increasing
the temperature by supplying the heat energy, the atoms are going away
from each other and they acquire space in between the atoms. Hence, the
strength of attraction is decreased, we can add some particles like
sugar in between the atoms of the liquid. So, there is no definite shape.
GASEOUS STATE OF THE MATTER
Water
vapor is an example of the gaseous state of the matter, the atoms are
very far away from each other, there is a lot of gap between the
particles. These gaseous particles move very easily and they can be
compressed easily. We can compress a large volume of gas in a cylinder.
arithmetic reasoning questions
1) 121, 225,361,?
2) 9,11,20,31,?82
3)35,7,36,14,37,21,?
4)1,2,8,14,?,34
5)2,3,5,7,11,?17
6)3,12,27,48,75,108
7)2,1,2,4,4,5,6,7,8,8,10,11,?
8)2,5,26,677,?
9)0,7,26,63,?
10)2,15,4,80,?
2) 9,11,20,31,?82
3)35,7,36,14,37,21,?
4)1,2,8,14,?,34
5)2,3,5,7,11,?17
6)3,12,27,48,75,108
7)2,1,2,4,4,5,6,7,8,8,10,11,?
8)2,5,26,677,?
9)0,7,26,63,?
10)2,15,4,80,?
Tuesday 22 November 2016
greatest common divisor
GCD
A divisor is another name of factor. A factor is a number which divides a given number completely with leaving a reminder zero.
Let us find all the factors of 10
Number 10 is divided by 1,2,5,10, So these four numbers are the factors of 10.
Let us take another example of 20
Number 20 is divided by 1,2,4,5,10,20
Now we are going to find out the great common divisor of 10,20
let us take all the common factors of 10 & 20
1,2,5,10
Among the common factors of 10 & 20, the greatest number which is factor to both the 10, 20 is 10.
Hence the greatest common divisor of 10, 20 is 10.
The meaning is 10 is only the number which divides equally both 10,20.
Friday 18 November 2016
least common multiple
least common multiple is the lowest number among the common multiples of the given numbers
for example.....
finding LCM of 2,4
solution:
step 1... Write all multiples of 2 and 4
step 2.... Write all the common multiples
step 3....write the lowest of common multiples
then the answer is ...
for example.....
finding LCM of 2,4
solution:
step 1... Write all multiples of 2 and 4
step 2.... Write all the common multiples
step 3....write the lowest of common multiples
then the answer is ...
Thursday 17 November 2016
USES OF PLANE AND CONCAVE MIRRORS
1. Plane mirrors are used as looking glass.
2. Plane mirrors are used by barbers to show front and back side of the customer head
3. Plane mirrors are used by scouts for signalling and also for army personnel.
4. Plane mirrors are used by the opticians to provide false dimension when their place of work is very small.
5. Plane mirrors are used for providing false dimensions in displaying jewellery, show cases, wrist watches, etc. These plane mirrors are fixed such that their mirrors are opposite to each other.
6. When the plane mirrors are opposite to each one, then they form multiple images, which makes a person happy by looking multiple images.
7. Plane mirrors are also used in cooking where the solar cookers are used.
8. Plane mirrors are used in making kaleidoscope.
uses of concave mirrors
1. concave mirrors are also used in solar cookers.
2. concave mirrors are used as a shaving mirror. The fundamental principle is when the object is in between pole of mirror and principal focus, then the image formed is virtual and erect and magnified (enlarged) image is formed, in this way the person image gets magnified.
3. Concave mirrors are also used as reflectors, generally concave mirrors are used in cars, trucks, motor bikes, in all these bikes, the bulb is placed at the principal focus of the concave reflector then a powerful parallel beam of light is formed.
4. Concave mirrors are used by doctors, especially by the doctors where we undergo examination for ear, throat, nose, teeth, etc. We observe at dentists, these are used to see the back of the tooth by placing it behind the tooth. Then a virtual, erect and enlarged image is formed.