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(i) When an object is immersed in a fluid, name the two forces acting on it. (ii) On which factor the magnitude of the upward force acting on this object depends ? (iii) When will this object sink?
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0
|
6571
|
July 1, 2016
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State Archimedes’principle. The following figures show three identical blocks of wood floating in three different liquids A, B and C of densities d1, d2, and d3 respectively. Which of these has the highest density ? Give reason to justify your answer
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1
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2329
|
July 1, 2016
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|
Define buoyant force.An object of volume 5 cm3 is immersed first in water and then in salt solution. In which case will it experience a greater buoyant force ? What will be the effect on the buoyant force, if the volume of the object is increased to 8 cm3
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0
|
1046
|
July 1, 2016
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The density of turpentine at 293 K is given as 870 kg m^-3. Identify and write the names of substances that sink in turpentine at the same temperature
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1
|
3480
|
July 1, 2016
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Ram places a piece of iron on the surface of water. What will happen ? Give reason
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0
|
1253
|
July 1, 2016
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|
(a) Distinguish between density and relative density of a substance. (b) The relative density of silver is 10.8. If the density of water is 103 kg m^-3, find the density of silver
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0
|
11971
|
July 1, 2016
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State Archimedes' Principle. A ball weighing 4 kg of density 4000 kg m^-3 is completely immersed in water of density 1000 kg m^-3. Find the apparent weight of the ball in water. (g = 10m s^-2)
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0
|
1562
|
July 1, 2016
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Explain the following : (i) Icebergs floating in the sea are dangerous for the ' ship. (ii) An egg sinks in freshwater but floats in a strong solution of salt. (iii) An iron nail sinks in water but a ship made of iron floats
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1
|
4529
|
July 1, 2016
|
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Define density and relative density. Give their mathematical formula and SI unit
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0
|
3382
|
July 1, 2016
|
|
Define pressure. Give its mathematical expression and its SI unit
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0
|
4765
|
July 1, 2016
|
|
The volume of 50 g of a substance is 20 cm^3. If the density of water is 1 g cm^-3, will the substance float or sink in water? Justify your answer
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0
|
364
|
July 1, 2016
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|
The mass of a block made of certain material is 13.5 kg and its volume is 15 x 10^-3 m^3. Will the block float or sink in water ? (Given that density of water is 1000 kg m^-3)
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0
|
2277
|
July 1, 2016
|
|
Why is the pressure on ground more when a man is walking than when he is standing?
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0
|
5184
|
July 1, 2016
|
|
What is meant by buoyancy? Draw a diagram to show two forces acting on an object floating half immersed in a liquid
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0
|
3248
|
July 1, 2016
|
|
The volume Of 50 g of a substance is 20 cm^3. If the density of water is 1 g m^-3, will the substance float or sink in water ? Justify your answer
|
|
0
|
2441
|
July 1, 2016
|
|
An iron cube of side 10 cm is kept on a horizontal table. If the density of iron is 8000 kg m~3. Find the pressure on the portion of the table where the cube is kept. (g = 10 ms^-2)
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0
|
1799
|
July 1, 2016
|
|
Give reason for the following: (i) Cutting and piercing toots are made sharp. (ii) An egg sinks in freshwater but floats in highly salty water
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0
|
1915
|
July 1, 2016
|
|
List two forces which act as on a body when it is immersed in a liquid. State the condition for a body to float or sink in a liquid. Why does an iron nail sink and a piece of wood floats when placed on the surface of water?
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0
|
2788
|
July 1, 2016
|
|
A) State the principle on which the working of a hydrometer is based. (b) A sharp knife is more effective than a blunt knife. Why?
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|
0
|
2253
|
July 1, 2016
|
|
The wheels of an army tank rest on a steel belt. Giife reason
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|
0
|
1588
|
July 1, 2016
|
|
Lead has greater density than iron and both are denser than water. Is the buoyant force on a lead object greater than, or lesser than or equal to the buoyant force on an iron object of the same volume ? Explain your answer giving reason
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|
0
|
1777
|
July 1, 2016
|
|
(a) A floating boat displaces water weighing 6000 N. (i) What is the buoyant force on the boat ? (ii) What is the weight of the boat ? (b) What happens to the buoyant force as more and more volume of a solid object is immersed in a liquid?
|
|
0
|
4720
|
July 1, 2016
|
|
(a) Why does a block of wood held underwater rise to the surface when released ? (b) An object of weight 200 N is floating in a liquid. What is the magnitude of buoyant force acting on it?
|
|
0
|
1160
|
July 1, 2016
|
|
(a) Explain why a truck or a motor bus has much tender tyres ? (b) Why do we feel lighter when we swim?
|
|
0
|
2137
|
July 1, 2016
|
|
Which will exert more pressure 100 kg mass on 10 m2 or 50 kg mass on 4 m2? Give reason
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|
0
|
6061
|
June 30, 2016
|
|
(a) Name the forces acting on a body, when it is fully or partially immersed in a liquid. (b) Briefly explain, why some objects float and some sink
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|
0
|
1737
|
June 30, 2016
|
|
What is Relative Density ? The relative density of a substance is greater than one, what does it signify?
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|
0
|
1115
|
June 30, 2016
|
|
What happens when : (a) Buoyant Force exerted by the fluid is less than the weight of the body ? (b) Buoyant Force exerted by the fluid is equal to the weight of the body?
|
|
0
|
1449
|
June 30, 2016
|
|
The volume of 40 g of a solid is 15 cm3. If the density of water is 1 g cm-3, will the solid float or sink ? Why?
|
|
0
|
2908
|
June 30, 2016
|
|
A steel needle sinks in water but a steel ship floats. Explain how
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|
0
|
8267
|
June 30, 2016
|