Q3 of 13 Page 22

Answer the following questions in brief.

A plastic cube is released in water. Will it sink or come to the surface of water?

An object sinks or float in water is decided by whether the buoyant force is greater than or lesser than that of weight of object in water. If buoyant force is greater than weight of object in water, object will float. If buoyant force is less than that of weight, object sinks.

Plastic cube in water has buoyant force greater than its weight in water. So, it floats on the surface of water.



More from this chapter

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1

Write proper word in the blank space.

(a) The SI unit of force is............... (Dyne, Newton, Joule)


(b) The air pressure on our body is equal to........... pressure. (Atmospheric, Sea bottom, Space)


(c) For a given object, the buoyant force in liquids of different.... is................ (the same, density, different, area)


(d) The SI unit of pressure is............... (N/m3,N/m2,kg/m2,Pa/m2)

 2

Make a match.

A group


1. Fluid


2. Blunt knife


3. Sharp needle


4. Relative density


5. Hecto Pascal


B group


a. Higher pressure


b. Atmospheric Pressure


c. Specific gravity


d. Lower pressure


e. same pressure in all directions

 3

Answer the following questions in brief.

Why do the load carrying heavy vehicles have large number of wheels?

 3

Answer the following questions in brief.

How much pressure do we carry on our heads? Why don’t we feel it?