Advertisements
Advertisements
प्रश्न
The relative density of lead is 11.3. Its density is ______ g cm–3or ______ kg m–3.
Advertisements
उत्तर १
The relative density of lead is 11.3. Its density is 11.3 g cm–3or 11.3 × 10-3 kg m–3.
Explanation:
Relative density of a lead is given by the relation,
`"Relative density" = "Density of lead"/"Density of water"`
Density of water = 1 g/cm3
Density of lead = Relative density of lead x Density of water
= 11.3 × 1
= 11.3 g/`"cm"^-3`
Again 1g = `1/1000` kg
`1 cm^3 = 10^(-6)"m"^3`
`1 "g/cm"^3 = 10^(-3)/10^(-6) "kg"/"m"^3 = 10^-3 "kg/m"^-3`
`:. 11.3 "g/cm"^-3 = 11.3 xx 10^-3 "kg/m"^-3`
उत्तर २
Density = 11.3 g/cm3
=11.3 × 103 kg m-3 [1 kg =103 g, 1 m = 102 cm]
=11.3 × 103 kg m-3
APPEARS IN
संबंधित प्रश्न
What do you mean by significant figures?
Round up the following upto three significant figures:
0.04597
A student measures the thickness of a human hair by looking at it through a microscope of magnification 100. He makes 20 observations and finds that the average width of the hair in the field of view of the microscope is 3.5 mm. What is the estimate on the thickness of hair?
The photograph of a house occupies an area of 1.75 cm2on a 35 mm slide. The slide is projected on to a screen, and the area of the house on the screen is 1.55 m2. What is the linear magnification of the projector-screen arrangement?
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.
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
Describe what is meant by significant figures.
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.
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 ______.
Using the rules for significant figures, the correct answer for the expression `(0.02858 xx 0.112)/(0.5702)` will be ______.
How many significant figures are present in the measurement 2007 grams?
Which of the following measurements contains exactly two significant figures?
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?
