+91-8076753736[email protected]
logo
logo
-->

Is Matter Around Us Pure

Question
CBSEENSC9006575
Wired Faculty App

A sound wave has a frequency of 2 kHz and wavelength 35 cm. How long will it take to travel 1.5 km?

Solution
Frequency comma space straight v space equals space 2 space kHz space equals space 2000 space Hz Wavelength comma space straight lambda space equals space 35 space cm space equals space 0.35 space straight m We space know space that space speed comma v space of space the space wave space equals space wavelength space cross times space frequency space i. e. comma space space space space space space space space space space space space space space space space space space space space space space space space space space space space space space space space space space space space space v space equals space λv space space space space space space space space space space space space space space space space space space space space space space space space space space space space space space space space space space space space space space space space space space space space space space space space space equals space 0.35 space straight m space cross times space 2000 space Hz space equals space 700 space straight m divided by straight s space space space space space space space space space space space space space space space space space space space space space space space space space space space space space space space
The time taken by the wave to travel a distance, d of 1.5 km is, 
straight t space equals space straight d over v space equals fraction numerator 1.5 space cross times space 1000 space straight m over denominator 700 space ms to the power of negative 1 end exponent end fraction space equals space 15 over 7 space straight s space equals space 2.1 space straight s.
Thus sound will take 2.1 s to travel a distance of 1.5 km.

Some More Questions From Is Matter Around Us Pure Chapter

Which separation techniques will you apply for the separation of the following?

Oil from water.

Which separation techniques will you apply for the separation of the following?

Tea leaves from tea

Which separation techniques will you apply for the separation of the following?

Iron pins from sand.

Which separation techniques will you apply for the separation of the following?

Wheat grains from husk

Which separation techniques will you apply for the separation of the following?


Fine mud particles suspended in water.

Write the steps you would use for making tea. Use the words—solution, solvent, solute, dissolve, soluble, insoluble, filtrate and residue.

Pragya tested the solubility of three different substances at different temperatures and collected the data as given below (results are given in the following table, as grams of substance dissolved in 100 grams of water to form a saturated solution).

Substance Dissolved

Temperature in K

283

293

313

333

353

Potassium nitrate

21

32

62

106

107

Sodium chloride

36

36

36

37

37

Potassium chloride

35

35

40

46

54

Ammonium chloride

24

37

41

55

66


What mass of potassium nitrate would be needed to produce a saturated solution of potassium nitrate in 50 grams of water at 313 K?

Pragya makes a saturated solution of potassium chloride in water at 353 K and leaves the solution to cool at room temperature. What would she observe as the solution cools? Explain.

Substance Dissolved

Temperature in K

283

293

313

333

353

Potassium nitrate

21

32

62

106

107

Sodium chloride

36

36

36

37

37

Potassium chloride

35

35

40

46

54

Ammonium chloride

24

37

41

55

66


Find the solubility of each salt at 293 K. Which salt has the highest solubility at this temperature?

Substance Dissolved

Temperature in K

283

293

313

333

353

Potassium nitrate

21

32

62

106

107

Sodium chloride

36

36

36

37

37

Potassium chloride

35

35

40

46

54

Ammonium chloride

24

37

41

55

66


Pragya tested the solubility of three different substances at different temperatures and collected the data as given below (results are given in the following table, as grams of substance dissolved in 100 grams of water to form a saturated solution).

Substance Dissolved

Temperature in K

283

293

313

333

353

Potassium nitrate

21

32

62

106

107

Sodium chloride

36

36

36

37

37

Potassium chloride

35

35

40

46

54

Ammonium chloride

24

37

41

55

66

What is the effect of change of temperature on the solubility of a salt?

Mock Test Series

Mock Test Series

NCERT Sample Papers

Entrance Exams Preparation