At some height, the density of air is less than that at the ground. The upthrust on the balloon is equal to its weight and the resultant force on the balloon is zero.
johnmulu answered the question on February 18, 2017 at 10:13
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State the law of flotation
(Solved)
State the law of flotation
Date posted:
February 18, 2017
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Answers (1)
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When a piece of metal is placed on water, it sinks. But when the same piece of metal is placed on a block of wood, both are found to float.
(Solved)
When a piece of metal is placed on water, it sinks. But when the same piece of metal is placed on a block of wood, both are found to float. Explain this observation.
Date posted:
February 18, 2017
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Answers (1)
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A block of glass of mass 250 g floats in mercury. What volume of glass lies under the surface of the mercury? (Density of mercury is 13.6 x 103Kgm-3)
(Solved)
A block of glass of mass 250 g floats in mercury. What volume of glass lies under the surface of the mercury? (Density of mercury is 13.6 x 103Kgm-3)
Date posted:
February 18, 2017
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Answers (1)
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A block of wood weighing 2.0 N is held under water by a string attached to the bottom of a container. The tension in the string is 0.5 N
(Solved)
A block of wood weighing 2.0 N is held under water by a string attached to the bottom of a container. The tension in the string is 0.5 N. Determine the density of the wood.
Date posted:
February 18, 2017
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Answers (1)
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Ice cubes float on water and solid benzene sinks in liquid benzene, Explain
(Solved)
Explain the following observation: Ice cubes float on water and solid benzene sinks in liquid benzene
Date posted:
February 18, 2017
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Answers (1)
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A solid copper sphere will sink in water while a hollow copper sphere of the same mass may float.
(Solved)
A solid copper sphere will sink in water while a hollow copper sphere of the same mass may float. Explain this observation.
Date posted:
February 18, 2017
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Answers (1)
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When a bus goes a round bend on a flat road, it experiences a centripetal force, State what provides the centripetal force and the purpose of banking roads at bends.
(Solved)
a) When a bus goes a round bend on a flat road, it experiences a centripetal force. State what provides the centripetal force
b) State the purpose of banking roads at bends.
Date posted:
February 18, 2017
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Answers (1)
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Explain applications of uniform circular motion in daily life.
(Solved)
Explain applications of uniform circular motion in daily life.
Date posted:
February 18, 2017
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Answers (1)
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State two ways in which the centripetal force on a body can be increased.
(Solved)
State two ways in which the centripetal force on a body can be increased.
Date posted:
February 18, 2017
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Answers (1)
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Define the term angular velocity
(Solved)
Define the term angular velocity
Date posted:
February 18, 2017
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Answers (1)
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A body mass 0.50 kg is attached to the end of a string of length 50 cm and Whirled in a horizontal circle. If the tension in the string is 81N, Determine the velocity of the body.
(Solved)
A body mass 0.50 kg is attached to the end of a string of length 50 cm and Whirled in a horizontal circle. If the tension in the string is 81N, Determine the velocity of the body.
Date posted:
February 18, 2017
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Answers (1)
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A car of mass 1200 kg is moving with a velocity of 25ms-1 around a flat bend of radius 150m. Determine the minimum frictional force between the tyres and the road that will prevent the car from sliding off
(Solved)
A car of mass 1200 kg is moving with a velocity of 25ms-1 around a flat bend of radius 150m. Determine the minimum frictional force between...
Date posted:
February 18, 2017
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Answers (1)
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Explain why a pail of water can be swung in vertical circle without the water pouring out.
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Explain why a pail of water can be swung in vertical circle without the water pouring out.
Date posted:
February 18, 2017
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Answers (1)
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State the meaning of the term “Principal focus” as applied in lenses
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The term principal focus is used in lenses. What does it mean?
Date posted:
February 18, 2017
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Answers (1)
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Define the term accommodation as applied to human eye
(Solved)
What is meant by the term accommodation with reference to the eye?
Date posted:
February 18, 2017
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Answers (1)
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An illuminated vertical object is initially placed on the principle axis of a converging lens and 32 cm from it
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An illuminated vertical object is initially placed on the principle axis of a converging lens and 32 cm from it. The focal length of the lens is 15 cm. The object is now placed at a point 12 cm from the lens and on the same side. State two changes other than magnification that are observed on the image formed due to this change.
Date posted:
February 18, 2017
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Answers (1)
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An object placed in front of a convex lens of focal length 10 cm produces an image at a distance of 15 cm from the lens and on the same side as the object.
(Solved)
An object placed in front of a convex lens of focal length 10 cm produces an image at a distance of 15 cm from the lens and on the same side as the object. Determine the position of the object.
Date posted:
February 18, 2017
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Answers (1)
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The pressure of the air inside a car tyre increases if the car stands out in the sun for some time on a hot day. Explain the pressure increase in terms of the kinetic theory of gases.
(Solved)
The pressure of the air inside a car tyre increases if the car stands out in the sun for some time on a hot day. Explain the pressure increase in terms of the kinetic theory of gases.
Date posted:
February 18, 2017
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Answers (1)
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A long horizontal capillary tube of uniform bore sealed at one end contains dry air trapped by a drop of mercury. The length of the air column is 142 mm at 17oC.
(Solved)
A long horizontal capillary tube of uniform bore sealed at one end contains dry air trapped by a drop of mercury. The length of the air column is 142 mm at 17oC. Determine the length of the air column at 25oC.
Date posted:
February 18, 2017
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Answers (1)
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In verifying the pressure law of gases, the temperature and pressure of a gas are varied at constant volume.
(Solved)
In verifying the pressure law of gases, the temperature and pressure of a gas are varied at constant volume. State the condition necessary for the law to hold.
Date posted:
February 18, 2017
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Answers (1)