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Differences
1. The focal length of the eye lens changes while that of the lens camera is constant.
2. The distance between the lens and film in a lens camera can be varied by zooming while the distance
between the eye lens and retina is constant.
3. A camera can take only one photo at a time when the shutter is open while the eye forms constantly
changing pictures.
Moraa orina answered the question on April 11, 2018 at 16:53
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and the magnification of the image....(Solved)
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is:
Date posted: April 11, 2018. Answers (1)
- A tin closed with an airtight lid contains air at a pressure of 1.0*25Pa at a temperature of 12^oC. If the temperature at which the...(Solved)
A tin closed with an airtight lid contains air at a pressure of 1.0*2
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Date posted: April 11, 2018. Answers (1)
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Date posted: April 11, 2018. Answers (1)
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A gas occupies a volume of 125cm3 at 150C and 755mmHg pressure. Find the volume of the gas at a
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Date posted: April 11, 2018. Answers (1)
- A gas occupies a volume of 1.6 cm3 at a pressure of 1.5 * 25 Pa. find the volume it will occupy at a pressure of...(Solved)
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Date posted: April 11, 2018. Answers (1)
- The speed of light in medium 1 is 8.0*28m/s and in medium 2 is 1.5*28m/s. Calculate the refractive index of medium 2 with respect to...(Solved)
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Date posted: April 10, 2018. Answers (1)
- The velocity of light in glass is 8.0*28m/s. Calculate:
a) The refractive index of glass
b) The angle of refraction in glass for a ray of light...(Solved)
The velocity of light in glass is 8.0*28m/s. Calculate:
a) The refractive index of glass
ss
b) The angle of refraction in glass for a ray of light incident at the air-glass interface at an angle of incidence of
40
Date posted: April 10, 2018. Answers (1)
- A ray of light from air passes successively through parallel layers of water, oil, glass and then into air again. If the refractive indices...(Solved)
A ray of light from air passes successively through parallel layers of water, oil, glass and then into air again. If the refractive indices of water, oil and glass are 4/3, 6/5 and 3/2 respectively and the angle of incidence in air is 600.
Calculate
i) The angle of refraction in water.
ii) The angle of incidence at the oil-glass interface.
Date posted: April 10, 2018. Answers (1)
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An aluminium tray of mass 400g containing 300g of water is placed in a refrigerator. After 80 minutes, the
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Date posted: April 10, 2018. Answers (1)
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Date posted: April 10, 2018. Answers (1)
- A block of ice of mass 40g at 0^oC is placed in a calorimeter containing 400g of water at 20^oC. Ignoring heat absorbed by the...(Solved)
A block of ice of mass 40g at 0^oC is placed in a calorimeter containing 400g of water at 20^oC. Ignoring heat
absorbed by the calorimeter, determine the final temperature of the mixture after all the ice has melted.
Take s.h.c.of water= 4200JKg-1K-1 and the s.l.h. of fusion of ice= 340, 000JKg-1.
Date posted: April 10, 2018. Answers (1)
- 3kg of hot water was added to 9kg of cold water at 2^oC and the resulting temperature was 20^oC.ignoring heat loss by the container, determine...(Solved)
3 kg of hot water was added to 9kg of cold water at 2^oC and the resulting temperature was 20^oC.ignoring
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1K-1.
Date posted: April 10, 2018. Answers (1)
- In an experiment to determine the specific heat capacity of a metal, a 20g of the metal was transferred from boiling water to a lagged...(Solved)
In an experiment to determine the specific heat capacity of a metal, a 20g of the metal was transferred
from boiling water to a lagged copper calorimeter containing cold water. The water was stirred and a
final steady temperature was realized. The following data was recorded:
-initial temperature of cold water and calorimeter =20^oC
-temperature of boiling water =99^oC
-final temperature of water, calorimeter and metal =23.7^oC
-mass of cold water plus calorimeter =130g
mass of calorimeter =50g
Take s.h.c. of water=4200JKg-1K-1, s.h.c. of copper=400JKg-1K-1.
Use the data above to determine:
Date posted: April 10, 2018. Answers (1)
- A certain block is heated such that its temperature is raised from 15^oC to 45^oC. calculate the amount of heat absorbed by the metal if...(Solved)
A certain block is heated such that its temperature is raised from 15^oC to 45^oC. calculate the amount of
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Date posted: April 10, 2018. Answers (1)
- A student heated 20Kg of water to a temperature of 80^oC. He then added x Kg of water at 15^oC and the final steady...(Solved)
A student heated 20Kg of water to a temperature of 80^oC. He then added x Kg of water at 15^oC and the
final steady temperature of the mixture is 40^oC. Given that the s.h.c. of water is 1.2Jg-1K-1, determine the value of x.
Date posted: April 10, 2018. Answers (1)
- 70g of a solid initially at 250C was carefully dropped into water in a calorimeter at 600C. If the final constant temperature of the water...(Solved)
70g of a solid initially at 25^oC was carefully dropped into water in a calorimeter at 60^oC. If the final
constant temperature of the water and the solid was 54^oC and the mass of water is 500g, determine the
specific heat capacity of the solid. Assume the heat absorbed by the calorimeter to be negligible. Take the s.h.c. of water = 4200JKg-1K-1.
Date posted: April 10, 2018. Answers (1)