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The process of the eye lens being adjusted to focus objects at various distances
johnmulu answered the question on February 18, 2017 at 09:02
- An illuminated vertical object is initially placed on the principle axis of a converging lens and 32 cm from it(Solved)
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. Answers (1)
- 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. Answers (1)
- 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. Answers (1)
- 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. Answers (1)
- 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. Answers (1)
- When the temperature of a gas in a closed container is raised, the pressure of the gas increases. Explain how the molecules of the gas cause the increase in pressure(Solved)
When the temperature of a gas in a closed container is raised, the pressure of the gas increases..
Date posted: February 18, 2017. Answers (1)
- What is meant by absolute zero temperature?(Solved)
Define what is absolute zero temperature.
Date posted: February 18, 2017. Answers (1)
- What is meant by an ideal gas?(Solved)
State what is meant by an ideal gas.
Date posted: February 18, 2017. Answers (1)
- A balloon is filled with air to volume of 200 ml at a temperature of 293 K. Determine the volume when the temperature rises to 353K at the same pressure.(Solved)
A balloon is filled with air to volume of 200 ml at a temperature of 293 K. Determine the volume when the temperature rises to 353K at the same pressure.
Date posted: February 18, 2017. Answers (1)
- State the law that relates the volume of a gas to the temperature of a gas.
(Solved)
Define the law that relates the volume of a gas to the temperature of a gas.
Date posted: February 18, 2017. Answers (1)
- When an inflated balloon is placed in a refrigerator it is noted that its volume reduces.(Solved)
When an inflated balloon is placed in a refrigerator it is noted that its volume reduces. Use the kinetic theory of gases to explain this observation
Date posted: February 18, 2017. Answers (1)
- Two identical containers A and B are placed on a bench. Container A is filled with oxygen gas and container B with hydrogen gas such that the two gases have equal masses(Solved)
Two identical containers A and B are placed on a bench. Container A is filled with oxygen gas and container B with hydrogen gas such that the two gases have equal masses. If the containers are maintained at the same temperature state with reason the container in which the pressure is higher
Date posted: February 18, 2017. Answers (1)
- Determine the pressure required to compress a gas in a cylinder initially at 20oC and at a pressure of 1.03 x 10-5 to one-eighth of its original volume.(Solved)
Determine the pressure required to compress a gas in a cylinder initially at 20oC and at a pressure of 1.03 x 10-5 to one-eighth of its original volume.
Date posted: February 18, 2017. Answers (1)
- What is the value of -20oC on the absolute temperature scale?(Solved)
What is the value of -20oC on the absolute temperature scale?
Date posted: February 18, 2017. Answers (1)
- A house in which a cylinder containing cooking gas is kept unfortunately catches fire. The cylinder explodes. Give an explanation for the explosion.(Solved)
A house in which a cylinder containing cooking gas is kept unfortunately catches fire. The cylinder explodes. Give an explanation for the explosion.
Date posted: February 18, 2017. Answers (1)
- In an experiment to determine the specific latent of vapourization of water, steam of mass 10 g at 100o ...(Solved)
In an experiment to determine the specific latent of vapourization of water, steam of mass 10 g at 100o is passed into 100 g of water initially at 20oC in a container of negligible heat capacity. The temperature of the water rises to 70oC.
(Take the specific heat capacity of water as 4.2 x 103J Kg-1 and boiling point of water as 100oC)
i) Determine the specific latent heat of vapourization of water
ii) State two sources of error in this experiment.
Date posted: February 18, 2017. Answers (1)
- Define the term specific latent heat of fusion.(Solved)
State the meaning of the term "specific latent heat of fusion."
Date posted: February 18, 2017. Answers (1)
- State why it is necessary to leave an air space in a closed glass bottle of water when it is to be kept in a refrigerator(Solved)
State why it is necessary to leave an air space in a closed glass bottle of water when it is to be kept in a refrigerator.
Date posted: February 18, 2017. Answers (1)
- When temperature of water reaches its boiling point, bubbles rise to the surface....(Solved)
When temperature of water reaches its boiling point, bubbles rise to the surface
i) State what is contained in the bubbles
ii) State the reason why bubbles rise to the surface only at the boiling point.
Date posted: February 18, 2017. Answers (1)
- Why it is advisable to use a pressure cooker for cooking at high altitudes (Solved)
Explain why it is advisable to use a pressure cooker for cooking at high altitudes
Date posted: February 18, 2017. Answers (1)