Available Answers

1. 1.

   Write true or false. Correct the false statements.

   1. The density of irregular solids can be determined with the help of a Eureka can.
   2. The drop in the level of water in a measuring cylinder when an object is placed in it gives the volume of the object.
   3. A Eureka can is a container with a spout near its bottom.
2. 2.

   Fill in the blanks.

   1. A wax candle ___________________ on water.
   2. The ratio of density of a substance to the density of water at 4°C is known as the _____________________ of the substance.
   3. A ____________________ is the instrument used to measure the relative density of liquids.
   4. Kerosene will float over in water because is density is _________________ than that of water.
   5. The density of sea water is __________________ than the density of distilled water.
3. 3.

   1. An irregular solid which when completely immersed in water displaces 10 ml. of water. The volume of the solid is
      1. 5 ml.
      2. 10 ml.
      3. 15 ml.
      4. 20 ml.
   2. Which of the following is the SI unit relative density?
      1. kg
      2. m
      3. kg/m³
      4. no unit
   3. Relative density is also known as
      1. density.
      2. gravity.
      3. specific gravity.
      4. mass.
   4. A device used to measure the relative density of a liquid is known as
      1. thermometer.
      2. hydrometer.
      3. barometer.
      4. spring balance.
   5. Which of the following substances has the greatest density?
      1. aluminum
      2. water
      3. oxygen
      4. air
   6. Which of the following liquids will float on water (density = 1 g/mL)
      1. sea water (density = 1.025 g/mL)
      2. honey (density = 1.42 g/mL)
      3. gasoline (density = 0.71 g/mL)
      4. glycerine (density = 1.26 g/mL)
   7. The markings on the hull of the ship that indicate the level to which the ship can be submerged in sea water are called.
      1. horizontal lines.
      2. vertical lines.
      3. skew line.
      4. Plimsoll lines.
   8. For a give rise in temperature, the increase in density is maximum in case of
      1. gases.
      2. liquids.
      3. solids.
      4. none of these
   9. When a substance is heated, its density
      1. decreases
      2. increases.
      3. remain the same.
      4. becomes zero.
   10. In convection currents, hot air moves
       1. upwards.
       2. downwards.
       3. to the left.
       4. to the right.
   11. Which of the following natural phenomena takes place due to convection currents?
       1. land breeze
       2. sea breeze
       3. westerlies
       4. all of these
4. 4.

   Fill in the blanks.

   1. The _____________________ of a substance is the ratio of its mass and volume.
   2. A ________________________ is a container with a spout below it top.
   3. A _______________________, a small glass bottle with a stopper having a fine capillary tube, is used to determine the density of liquids.
   4. An iron ball will _______________________ in water.
   5. Both liquids and gases are together known as ______________________.
   6. Icebergs _____________________ in sea water.
   7. A lactometer is an instrument used to test the purity of _________________________.
   8. The relative density of a substance is the ratio of its density to the density of water at _______________________.
   9. When a substance is heated, its _________________ increases.
5. 5.

   Write true or false. Correct the false statements.

   1. The density of gases is more than that of solids.
   2. The volume of any liquid completely filled in a relative density bottle remains the same.
   3. We need to know only the mass of the substance to determine its relative density.
   4. Kerosene is lighter than water.
   5. The density of a substance is the ratio of its density to the density of water at 4°C.
   6. On multiplying the relative density by 1000, one gets the density of a substance in kg/m³.
   7. A  body of density 3-5 g/cm³ will float on water.
   8. The base of the bulb of the hydrometer is filled with lead so that the hydrometer can float in a horizontal position.
   9. Convection currents occur due to differences in density in different sections of a liquid or gas.
   10. A land breeze arises due to the differential heating between land and water surfaces.
6. 6.

   Match the columns.

   1. Mass	a. relative density bottle
   2. Volume	b. lactometer
   3. Sea breeze	c. Eureka can
   4. Density of milk	d. physical balance
   5. Relative density	e. convection currents