Today we are going to do the first chapter measurement in science and technology of your book.
We will tell you the important questions and answers of this chapter if you do this question and answer only. So there will be no need any Book
Measurement In science And technology
Question 1. What is a unit? Also tell the characteristics of the unit?
Ans The universal definition of unit is as follows. A fixed value is given to measure any physical quantity. This fixed value is called a unit.
For example, the kilogram unit is used to measure mass. Its fixed value is 100 grams.
Apart from this, kilometers are used to measure distance. Its fixed value is 1000 m.
Features of the unit
A unit has the following characteristics.
1. Well defined – The unit is well defined. This is its first feature. For example, the value of kilogram is 1000 grams. It is defined. No one can change it.
2. Convenient– The unit is convenient. that is, there is no exception
3. Corresponding – The unit is also compatible. This is its final quality.
Question 2. What is measurement?
Ans: Expressing the quantity of any physical quantity in numbers is called measurement. This is the universal definition of measurement.
The measurement process is completed with the help of scale. There are different types of scales for different elements. For example:- mass in kilogram, distance in kilometer, etc.
question. 3 Why do we need measurements?
Ans. Measurement is required. The reason for that is the following.
1. In daily lifestyle– First of all, measurement is an important part of our daily activities. For example, we go to the market. So there we measure vegetables in kilograms.
We have to go somewhere. So we estimate the distance in kilometers.
So we can say like this. Measurement is essential in our daily activities.
2. Scientific importance – Measurement also has scientific importance. Scientists do all physical conjecture like rockets. Sending to space etc. is done only with the help of measurement.
On the basis of this daily and scientific importance, we can say. measurement is required.
Question 5What is S.I prefix (S.I prefix)? Explain with example
Ans As we have just read S.I means. Basic units in which kilogram, kilometer, ampere, kandela, kelvin, second, mole etc. are included.
Meaning of prefix. which are placed in front of the word.
That is, according to this the definition of si perfix is there. Which is put in front of Si Unit. It is mainly used to represent large physical values. Is.
For example, the radius of the Sun is 696,340 km. We can easily write this as 696X 108 with the help of si perfix.
That is, the use of these prefixes and Ghats is said to express big values.
Question 4 What is S.I prefix (S.I prefix)? Explain with example
Ans As we have just read S.I means. Basic units in which kilogram, kilometer, ampere, kandela, kelvin, second, mole etc. are included.
Meaning of prefix. which are placed in front of the word.
That is, according to this the definition of si perfix is there. Which is put in front of Si Unit. It is mainly used to represent large physical values. Is.
For example, the radius of the Sun is 696,340 km. We can easily write this as 696X 108 with the help of si perfix.
That is, the use of these prefixes and Ghats is said to express big values.
Question – 05 S. State three main rules for writing units?Ans. Following are the three main rules for writing S I units.
1. Decimal representation in the beginning – Before writing those numbers whose value is less than 1, it is necessary to represent the decimal. Example :- 0.958 like this
2. Do not use full stop – Do not use full stop after the end of the sentences.
3. Giving space between units and amounts – It is necessary to give space between quantities and amounts. Example :- 10 kg is correct. Whereas 10kg is wrong.Question 6 What are the basic units?
Ans. (1) Those units which are independent of each other. That is, those which cannot be changed from each other, which do not have any relation with each other, they are called basic units.
(2) In the international system (S.I Unite) only 7 units have been given the title of basic units. Some of which are described as follows.
1. Unit of Length – Kilometer
2. Unit of mass – kilogram
3. Unit of Time – Second
4. Unit of temperature – Kelvin
5. Unit of electric current – ampere
6. The unit of the amount of a substance
– in moles
7. Light intensity– in candela
Derivation units
(1) Derived units are not independent, but they are made with the help of basic units (S.I units).
(2) They are defined with the help of basic units only. (3) The basic unit (S.I Unite) is only seven. Whereas derived units can be made unlimited. You can understand through this example. How are the derivative units made?
Area – Unit of Length X Unit of Breadth = meter X meter = meter2
The above description accurately describes the basic unit and the derived unit. And explain the difference between the two.