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i) To evacuate the bell jar OR
To pump air in and out of the bell jar
ii) The electric bell starts ringing but its sound as heard from outside the bell jar reduces in intensity and diminishes. This is because as the air is pumped out, the density of air in the bell jar reduces. As this continues a vacuum is created
in the bell jar which cannot transmit sound hence the sound get diminished
iii) - It is not possible to create vacuum in the bell jar
- Some sound is transmitted through the connecting wires and the walls of the bell jar.
Kavungya answered the question on October 30, 2019 at 12:35
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i)A mechanical wave.
ii)A longitudinal wave.(Solved)
Sound is a mechanical longitudinal wave. Explain why sound is classified as;
i)A mechanical wave.
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Date posted: October 30, 2019. Answers (1)
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ii)Calculate the focal length of the lens.
Date posted: October 30, 2019. Answers (1)
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Date posted: October 30, 2019. Answers (1)
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Diffraction is not a common phenomenon in light. Explain why.
Date posted: October 30, 2019. Answers (1)
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Date posted: October 30, 2019. Answers (1)
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Date posted: October 30, 2019. Answers (1)
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Sketch the path of the ray on the diagram after...(Solved)
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Date posted: October 30, 2019. Answers (1)
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Date posted: October 30, 2019. Answers (1)
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In an experiment to determine the specific latent heat of vaporization of water, steam at 1000C was passed into water contained in a well lagged copper calorimeter. The following measurements were made:
- Mass of calorimeter = 55g
- Initial mass of water = 75g
-Final mass of calorimeter + water + condensed steam = 133g
- Final temperature of the mixture = 300C.
Specific heat capacity of water = 4200J/Kg/K.
Specific heat capacity of copper = 390J/Kg/K.
Determine the:
i)Mass of condensed steam
ii)Heat gained by the calorimeter and water if the initial temperature of the calorimeter
+ water = 200C
iii)Given that L is the specific latent heat of vaporization of steam.
(I)Write an expression for the heat given out by steam.
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Date posted: October 30, 2019. Answers (1)
- The figure below shows a simple machine being used to raise a load W by applying an effort E.
i)Name the machine.
ii)Show that the velocity...(Solved)
The figure below shows a simple machine being used to raise a load W by applying an effort E.
i)Name the machine.
ii)Show that the velocity ratio (V.R) of the machine is given by R/r
iii)Given that r =11cm and R = 99cm, determine the effort E required to raise a load of 2800N
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Date posted: October 30, 2019. Answers (1)
- Figure below shows dots which were made by a ticker timer tape attached to a trolley.
If the frequency used was 50Hz, determine;
a)The velocities between AB...(Solved)
Figure below shows dots which were made by a ticker timer tape attached to a trolley.
If the frequency used was 50Hz, determine;
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Date posted: October 30, 2019. Answers (1)
- Figure below shows a uniform metre rule balancing when a mass of 200g is hung at one end.
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Date posted: October 30, 2019. Answers (1)
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Date posted: October 30, 2019. Answers (1)
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Describe the motion of the body between points:
OA
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Describe the motion of the body between points:
OA
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Date posted: October 30, 2019. Answers (1)
- The figure below shows a measuring cylinder which contains water initially at a level A.
A spherical solid is immersed in the water and the level...(Solved)
The figure below shows a measuring cylinder which contains water initially at a level A.
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Determine the diameter of the spherical ball.
Date posted: October 30, 2019. Answers (1)
- Explain why a porridge in a cup wrapped with a wet cloth cools faster than when the cup is dipped in cold water.(Solved)
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Date posted: October 28, 2019. Answers (1)
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ii)State the purpose of the bromine gas in the tube.(Solved)
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Date posted: October 17, 2019. Answers (1)
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(Take the plank’s constant to be 6.6 x 10-34 J)
(Solved)
Sodium has work function of 2.42eV. Calculate its threshold frequency.
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Date posted: October 17, 2019. Answers (1)
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ii)Give reasons for the changes in the e.m.f as the coil rotates from 00 to 1800.
Date posted: October 17, 2019. Answers (1)
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Date posted: October 17, 2019. Answers (1)