Advertisements
Advertisements
Question
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
Advertisements
Solution 1
Wind speed during a storm can be measured by an anemometer. As wind blows, it rotates. The rotation made by the anemometer in one second gives the value of wind speed.
Solution 2
Wind speed can be estimated by floating a gas-filled balloon in air at a known height h. When there is no wind, the balloon is at A. Suppose the wind starts blowing to the right such that the balloon drifts to position B in 1 second.
Now, AB = d = hθ.

The value of d directly gives the wind speed.
RELATED QUESTIONS
How many significant figures are present in the 2.0034?
How many significant figures should be present in the answer of the following calculation?
0.0125 + 0.7864 + 0.0215
The mean diameter of a thin brass rod is to be measured by vernier callipers. Why is a set of 100 measurements of the diameter expected to yield a more reliable estimate than a set of 5 measurements only?
The mass of a box measured by a grocer’s balance is 2.300 kg. Two gold pieces of masses 20.15 g and 20.17 g are added to the box. What is
- What is the total mass of the box?
- What is the difference in the masses of the pieces to correct significant figures?
State the number of significant figures in the following:
6.320 J
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.
The diameter of a sphere is 2.14 cm. Calculate the volume of the sphere to the correct number of significant figures.
Answer the following question.
Describe what is meant by order of magnitude.
The radius of the circle is 3.12 m. Calculate the area of the circle with regard to significant figures.
Write the rules for determining significant figures.
The number of significant figures in 0.06900 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?
How many significant figures are present in the measurement 2007 grams?
What is the least count of a measuring instrument?
Which of the following numbers has 4 significant figures?
Which of the following statements is correct about significant figures and accuracy?
A length L is measured as 125 m, which is also written as 12500 cm and 125000 mm. How many significant figures does this measurement have?
