Advertisements
Advertisements
प्रश्न
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.
Advertisements
उत्तर
| Number | No. of significant figures | Reason |
| 0.003 m2 | 1 | Rule no. iii |
| 0.1250 g cm-2 | 4 | Rule no. iv |
| 6.4 × 106 m | 2 | Rule no. i |
| 1.6 × 10-19 C | 2 | Rule no. i |
| 9.1 × 10-31 kg | 2 | Rule no. i |
APPEARS IN
संबंधित प्रश्न
What do you mean by significant figures?
How many significant figures are present in the 500.0?
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
You are given a thread and a metre scale. How will you estimate the diameter of the thread?
Precise measurements of physical quantities are a need of science. For example, to ascertain the speed of an aircraft, one must have an accurate method to find its positions at closely separated instants of time. This was the actual motivation behind the discovery of radar in World War II. Think of different examples in modern science where precise measurements of length, time, mass etc. are needed. Also, wherever you can, give a quantitative idea of the precision needed.
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.
A SONAR (sound navigation and ranging) uses ultrasonic waves to detect and locate objects under water. In a submarine equipped with a SONAR the time delay between generation of a probe wave and the reception of its echo after reflection from an enemy submarine is found to be 77.0 s. What is the distance of the enemy submarine? (Speed of sound in water = 1450 m s–1).
State the number of significant figures in the following:
0.007 m2
State the number of significant figures in the following:
2.64 × 1024 kg
State the number of significant figures in the following:
0.0006032 m2
Solve the numerical example.
Nuclear radius R has a dependence on the mass number (A) as R =1.3 × 10-16 A1/3 m. For a nucleus of mass number A = 125, obtain the order of magnitude of R expressed in the meter.
Solve the numerical example.
The diameter of a sphere is 2.14 cm. Calculate the volume of the sphere to the correct 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 mass and volume of a body are 4.237 g and 2.5 cm3, respectively. The density of the material of the body in correct 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 ______.
Which of the following measurements has exactly two significant figures?
Which of the following measurements contains exactly two significant figures?
Which of the following statements is correct about significant figures and accuracy?
