Question
Question: The thickness of the newspaper sheet is of the order of \(\begin{array}{l} {\rm{A}}{\rm{. 0}}{\r...
The thickness of the newspaper sheet is of the order of
A.0.1m B.0.1cm C.0.1mm D.1micrometre
Solution
The thickness of a solid is the measure of the smallest distance of solid, its SI unit is a metre(m). Observe from your surroundings, the units defined for different objects and match the accurate unit with the question asked.
Complete step-by-step answer :
The size of the objects in the universe varies from very very small of the order of 10−24 to very large of the order of 10+24. We use various methods and objects to calculate them such as: the parallax method for the measurement of large distances, use of instruments such as screw gauge, Vernier callipers, optical microscope and other methods for measuring very small size.
Here, we use screw gauge to measure the thickness of the sheet of a paper accurately and it is found to be of the order of 0.1 mm, but some magazine thickness may be of the order of 0.1 m.
So the more accurate answer is option C.
Additional Information :
1. As every measurement involves errors, to remove ambiguities in measurement, the best way to report them is in the “power of 10”, we call it “scientific notation”.
2. Generally, it is written as -
a×b10
Where, a – coefficient which is a number between 0-9.
10 – is a base (decimal system).
b – is an exponent.
3. Its dimensional formula is [L].
4. The screw gauge is an instrument used for measuring accurately the diameter of a thin wire, the thickness of a sheet of metal or the sheet of paper.
Note :Students should remember these points while answering these types of questions: -
1. Some powers of 10 have special prefixes which are written in front of SI units.
2. Some of them which are mentioned in the above question prefixes values and its symbols are given below -
10−2−centi (c)
10−3- milli (m)
10−6 - micro (µ)
3. Least count is the smallest distance that can be measured using the instrument-
For screw gauge it is = 0.01mm
For Vernier callipers = 0.01cm
4. So, the screw gauge can measure the thickness of paper accurately then Vernier callipers.