Advertisements
Advertisements
प्रश्न
Why do we have different units for the same physical quantity?
Advertisements
उत्तर
The value of any given physical quantity may vary over a wide range, therefore, different uns of the same physical quantity are required. e.g., The length of a pen can be easily measured in cm, the height of a tree can be measured in metres, the distance between two cities can be measured in kilometres and the distance between two heavenly bodies can be measured in light years.
APPEARS IN
संबंधित प्रश्न
How many significant figures are present in the 5005?
How many significant figures should be present in the answer of the following calculation:-
`(0.02856 xx 298.15 xx 0.112)/0.5785`
How many significant figures should be present in the answer of the following calculation?
5 × 5.364
How many significant figures should be present in the answer of the following calculation?
0.0125 + 0.7864 + 0.0215
A man walking briskly in rain with speed v must slant his umbrella forward making an angle θ with the vertical. A student derives the following relation between θ and v: tan θ = v and checks that the relation has a correct limit: as v →0, θ → 0, as expected. (We are assuming there is no strong wind and that the rain falls vertically for a stationary man). Do you think this relation can be correct? If not, guess the correct relation.
State the number of significant figures in the following:
0.2370 g cm–3
State the number of significant figures in the following:
0.0006032 m2
Just as precise measurements are necessary in science, it is equally important to be able to make rough estimates of quantities using rudimentary ideas and common observations. Think of ways by which you can estimate the following (where an estimate is difficult to obtain, try to get an upper bound on the quantity):-
the wind speed during a storm
Solve the numerical example.
A large ball 2 m in radius is made up of a rope of square cross-section with edge length 4 mm. Neglecting the air gaps in the ball, what is the total length of the rope to the nearest order of magnitude?
Solve the numerical example.
Write down the number of significant figures in the following: 0.003 m2, 0.1250 gm cm-2, 6.4 x 106 m, 1.6 x 10-19 C, 9.1 x 10-31 kg.
Which of the following has the highest number of significant figures?
Write the rules for determining significant figures.
Write a short note on the following.
Rounding - off
If the density of a solution is 3.12 g mL–1, the mass of 1.5 mL solution in significant figures is ______.
The sum of the numbers 436.32, 227.2 and 0.301 in appropriate significant figures is ______.
The numbers 2.745 and 2.735 on rounding off to 3 significant figures will give ______.
Using the rules for significant figures, the correct answer for the expression `(0.02858 xx 0.112)/(0.5702)` will be ______.
Significant figures in a measurement include which of the following?
Which of the following measurements has exactly two significant figures?
Which of the following measurements contains exactly two significant figures?
