Advertisements
Advertisements
प्रश्न
A wooden cube of side 10 cm has a mass of 700 g. It will float in the water with:
(a) Half of its volume inside the water
(b) 3 cm height above the water surface
(c) 7 cm height above the water surface
(d) Just inside the water surface.
Advertisements
उत्तर
Side of wooden cube = 10 cm.
Volume of wooden cube = 10 × 10 × 10 = 1000 cm3.
Mass of wooden cube = 700 g.
Density of wooden cube = mass/volume = 700/1000 = 0.7 gcm-3.
Density of water = 1 gcm-3.
(Density of floating body / Density of liquid) = fraction submerged
0.7/1 =fraction submerged
The fraction of wooden cube submerged in water = 0.7
Height of wooden cube = 10 cm
Part of wooden cube which is submerged = 10 × 0.7 = 7 cm
So, a wooden cube will float in the water with a 3 cm height above the water surface.
APPEARS IN
संबंधित प्रश्न
A body of volume 100 cm3 weighs 5 kgf in air. It is completely immersed in a liquid of density 1.8 × 103 kg m-3. Find:
- The upthrust due to liquid and
- The weight of the body in liquid.
Complete the following sentence.
Density of water is .... ... kg m-3.
The density of copper is 8.83 g cm-3. Express it in kg m-3.
A jeweller claims that he makes ornaments of pure gold that has a relative density of 19.3. He sells a bangle weighing 25.25 gf to a person. The clever customer weighs the bangle when immersed in water and finds that it weighs 23.075 gf in water. With the help of suitable calculations, find out whether the ornament is made of pure gold or not.
[Hint : calculate R.D. of material of bangle which comes out to be 11.6].
What can you say about the average density of a ship floating on water in relation to the density of water?
Explain the following :
A balloon filled with hydrogen rises to a certain height and then stops rising further.
A hollow cylinder of copper of length 25 cm and area of cross-section 15 cm2, floats in water with 3/5 of its length inside water. Calculate:
(1) apparent density of a hollow copper cylinder.
(2) wt. of cylinder.
(3) extra force required to completely submerge it in water.
A solid body weighs 2.10 N. in air. Its relative density is 8.4. How much will the body weigh if placed
(1) in water,
(2) in liquid of relative density 1.2?
Select the correct option:
The SI unit of density is:
Write the SI units of Weight of a body
