When air is blown over the mouth of the container, the pressure above the container reduces and its atmospheric pressure pushes the pith ball upwards.
Kavungya answered the question on May 25, 2019 at 08:13
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Sketch a velocity – time graph for a body initially moving at a velocity u before a force F is applied to it for 5...
(Solved)
Sketch a velocity – time graph for a body initially moving at a velocity u before a force F is applied to it for 5 seconds and there after the force F is withdrawn.
Date posted:
May 25, 2019
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Answers (1)
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A turntable of radius 16cm is rotating at 960 revolutions per minute. Determine the angular speed of the turntable.
(Solved)
A turntable of radius 16cm is rotating at 960 revolutions per minute. Determine the angular speed of the turntable.
Date posted:
May 25, 2019
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Answers (1)
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A bus that carries goods in the under seats carrier is more stable than one that carries goods in the carrier at the top. Explain...
(Solved)
A bus that carries goods in the under seats carrier is more stable than one that carries goods in the carrier at the top. Explain why this is so.
Date posted:
May 25, 2019
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Answers (1)
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The figure below shows two identical containers A and B containing hot water and ice block.
State with reason which water cools faster assuming that the...
(Solved)
The figure below shows two identical containers A and B containing hot water and ice block.
State with reason which water cools faster assuming that the wire gauge absorbs negligible heat.
Date posted:
May 25, 2019
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Answers (1)
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The diagram below shows a section of a micrometer screw gauge.
a) State the smallest measurement that can be made by the measurement that can be...
(Solved)
The diagram below shows a section of a micrometer screw gauge.
a) State the smallest measurement that can be made by the measurement that can be made by the micrometer screw gauge.
b) The thimble of the micrometer screw gauge is rotated through 2 ½ revolutions in the clockwise direction in order to
measure the diameter of a marble. State the diameter of the marble.
Date posted:
May 25, 2019
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Answers (1)
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The figure below shows a wire wound on a metal rod. The windings just touch each other. If the total number of complete loops was...
(Solved)
The figure below shows a wire wound on a metal rod. The windings just touch each other. If the total number of complete loops was found to be 25 and the distance covered by the windings on the rod is 0.6cm, find the radius of the wire giving your answer in standard form.
Date posted:
May 25, 2019
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Answers (1)
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Calculate the critical angle of a ray of light passing from glass to water, if their refractive indices are 2/3 and 4/3 respectively.
(Solved)
Calculate the critical angle of a ray of light passing from glass to water, if their refractive indices are 2/3 and 4/3 respectively.
Date posted:
May 25, 2019
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Answers (1)
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Explain why large convex mirrors are placed at certain points in supermarket
(Solved)
Explain why large convex mirrors are placed at certain points in supermarket
Date posted:
May 25, 2019
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Answers (1)
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An object 2.5 m tall is at a point 8m from a pinhole camera. If the distance of the screen is 8.16m from the object,...
(Solved)
An object 2.5 m tall is at a point 8m from a pinhole camera. If the distance of the screen is 8.16m from the object, calculate the size of the image
Date posted:
May 25, 2019
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Answers (1)
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The figure below shows a simple generator and the arrows indicate the direction of induced current.
(i) What type of generator is shown above ?
(ii)...
(Solved)
The figure below shows a simple generator and the arrows indicate the direction of induced current.
(i) What type of generator is shown above ?
(ii) State two ways of increasing the brightness of the bulb.
(iii) If the bulb was replaced by a CRO sketch on the axes provided a graph to show the variation of output emf with position of the coil starting from vertical position.
Date posted:
May 25, 2019
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Answers (1)
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Calculate the photon energy in ultraviolet radiation whose frequency is 8.60 x 1014 Hz. (Plank’s constant h=6.63 x 10-34 Js)
(Solved)
Calculate the photon energy in ultraviolet radiation whose frequency is 8.60 x 1014 Hz. (Plank’s constant h=6.63 x 10-34 Js)
Date posted:
May 25, 2019
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Answers (1)
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In an experiment to find the relationship between frequency of radiation and kinetic energy of photoelectrons in a photoelectric device, the following graph was obtained.
Use...
(Solved)
In an experiment to find the relationship between frequency of radiation and kinetic energy of photoelectrons in a photoelectric device, the following graph was obtained.
Use the graph to answer the following questions,
i) Determine the threshold frequency.
ii) Find the plank's constant h. .(Take the charge of an electron to be 1.6 x 10-19 C)
iii) Calculate the work function of the metal in joules.
Date posted:
May 25, 2019
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Answers (1)
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A wire of resistance 27 ohms is cut into three equal lengths. If the three wires are connected in parallel, what is the effective resistance?
(Solved)
A wire of resistance 27 ohms is cut into three equal lengths. If the three wires are connected in parallel, what is the effective resistance?
Date posted:
May 25, 2019
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Answers (1)
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The initial mass of a radioactive substance is 40g. The substance has a half-life of 10 years. Determine the mass remaining after 40 years.
(Solved)
The initial mass of a radioactive substance is 40g. The substance has a half-life of 10 years. Determine the mass remaining after 40 years.
Date posted:
May 25, 2019
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Answers (1)
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Sketch the magnetic field pattern of the following arrangement.
(Solved)
Sketch the magnetic field pattern of the following arrangement.
Date posted:
May 25, 2019
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Answers (1)
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A sharp point of a pin is held over a positively charged electroscope. State and explain the observation made on the electroscope.
(Solved)
A sharp point of a pin is held over a positively charged electroscope. State and explain the observation made on the electroscope.
Date posted:
May 25, 2019
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Answers (1)
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The figure below shows a ray of light incident on a glass prism.
Given that the critical angle for the glass is 390, sketch on the...
(Solved)
The figure below shows a ray of light incident on a glass prism.
Given that the critical angle for the glass is 390, sketch on the diagram the path of the ray through the prism.
Date posted:
May 25, 2019
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Answers (1)
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State why parabolic reflectors are used in car headlights
(Solved)
State why parabolic reflectors are used in car headlights.
Date posted:
May 22, 2019
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Answers (1)
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The figure below shows the path of a ray of light through a glass prism. The speed of yellow
light in the prism is 1.88 ×...
(Solved)
The figure below shows the path of a ray of light through a glass prism. The speed of yellow
light in the prism is 1.88 × 108m/s.
(i) Determine the refractive index of the prism material for the light (speed of light in vacuum, c
= 3.0 × 108m/s.
(ii) Show on the figure, the critical angle, c, and determine its value.
(iii) Given that r = 21.2º, determine the angle θ.
Date posted:
May 22, 2019
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Answers (1)
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The echo sounder of a ship receives the reflected wave from a sea-bed after 0.2 seconds.
What is the depth of the sea bed if the...
(Solved)
The echo sounder of a ship receives the reflected wave from a sea-bed after 0.2 seconds.
What is the depth of the sea bed if the velocity of sound in water is 1450m/s.
Date posted:
May 22, 2019
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Answers (1)