S.I. units are logical and coherent.
S.I. system of units is a rationalised system.
- If both the assertion and reason are true and reason is a correct explanation of the assertion
- If both assertion and reason are true but assertion is not a correct explanation of the assertion
- If the assertion is true but the reason is false
- If both assertion and reason are false
The Correct Option is B
Solution and Explanation
Top Questions on Units and measurement
- The pitch of an error free screw gauge is 1 mm and there are 100 divisions on the circular scale. While measuring the diameter of a thick wire, the pitch scale reads 1 mm and 63rd division on the circular scale coincides with the reference line. The diameter of the wire is:
- NEET (UG) - 2024
- Physics
- Units and measurement
- The potential energy of a particle moving along the x-direction varies as:
\[ V = \frac{Ax^2}{\sqrt{x} + B} \]
The dimensions of \(\frac{A^2}{B}\) are:- NEET (UG) - 2024
- Physics
- Units and measurement
- Least count of a vernier caliper is \( \frac{1}{20N} \, \text{cm} \).The value of one division on the main scale is \(1 \, \text{mm}\). Then the number of divisions of the main scale that coincide with \(N\) divisions of the vernier scale is:
- JEE Main - 2024
- Physics
- Units and measurement
- Given below are two statements:
Statement (I): Dimensions of specific heat is $[L^{2}T^{-2}K^{-1}]$
Statement (II): Dimensions of gas constant is $[M L^{2}T^{-2}K^{-1}]$- JEE Main - 2024
- Physics
- Units and measurement
- In a vernier calliper, when both jaws touch each other, zero of the vernier scale shifts towards left and its $4^\text{th}$ division coincides exactly with a certain division on the main scale. If 50 vernier scale divisions equal to 49 main scale divisions and zero error in the instrument is 0.04 mm, then how many main scale divisions are there in 1 cm?
- JEE Main - 2024
- Physics
- Units and measurement
Questions Asked in AIIMS exam
Given below are two statements, one is labelled as Assertion A and the other is labelled as Reason R
Assertion (A) : 02 is liberated in the non-cyclic photophosphorylation.
Reason (R) : Liberation of oxygen is due to photolysis of water.
In the light of the above statements, choose the correct answer from the options given below
- AIIMS - 2019
- Photosynthesis in higher plants
- Match the following column I with column II.
- AIIMS - 2019
- cloning
Given below are two statements, one is labelled as Assertion A and the other is labelled as Reason R
Assertion (A) : The Cro-Magnon man was the direct ancestor of the living modern man.
Reason (R) : Cro-Magnon man had slightly prognathous face.
In the light of the above statements, choose the correct answer from the options given below
- AIIMS - 2019
- evolution
- Given below are two statements, one is labelled as Assertion A and the other is labelled as Reason R
Assertion: Orbit of a satellite is within the gravitational field of earth whereas escaping is beyond the gravitational field of earth.
Reason: Orbital velocity of a satellite is greater than its escape velocity.
In the light of the above statements, choose the correct answer from the options given below- AIIMS - 2019
- Gravitation
Given below are two statements, one is labelled as Assertion A and the other is labelled as Reason R
Assertion (A) : In eukaryotes, transcription occurs in nucleus.
Reason (R) : In bacteria, transcription and translation occurs in cytoplasm.
In the light of the above statements, choose the correct answer from the options given below
- AIIMS - 2019
- Transcription
Concepts Used:
Units and Measurement
Unit:
A unit of a physical quantity is an arbitrarily chosen standard that is broadly acknowledged by the society and in terms of which other quantities of similar nature may be measured.
Measurement:
The process of measurement is basically a comparison process. To measure a physical quantity, we have to find out how many times a standard amount of that physical quantity is present in the quantity being measured. The number thus obtained is known as the magnitude and the standard chosen is called the unit of the physical quantity.
Read More: Fundamental and Derived Units of Measurement
System of Units:
- CGS system
- FPS system
- MKS system
- SI units
Types of Units:
Fundamental Units -
The units defined for the fundamental quantities are called fundamental units.
Derived Units -
The units of all other physical quantities which are derived from the fundamental units are called the derived units.