1. A ray close and parallel to the the principal axis is reflected through the principal focus.
2. A ray travelling through the principal focus or appearing to be passing through the principal focus is reflected parallel to the principal axis.
chrispohmomanyi answered the question on September 19, 2017 at 12:07
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A car can be brought to rest from a speed of 20 ms-1 in a time of 2s.
(i) Calculate the average deceleration
(ii) If the driver’s...
(Solved)
A car can be brought to rest from a speed of 20 ms-1 in a time of 2s.
(i) Calculate the average deceleration
(ii) If the driver’s reaction time is 0.2s, determine the shortest stopping distance
Date posted:
September 19, 2017
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Answers (1)
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State how eddy currents are reduced in a transformer
(Solved)
How are eddy currents in the transformer minimized?
Date posted:
September 19, 2017
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Answers (1)
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State three factors that affect the speed of sound in the air
(Solved)
State three factors that affect the speed of sound in the air
Date posted:
September 19, 2017
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Answers (1)
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Define the term wave
(Solved)
Define the term wave
Date posted:
September 19, 2017
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Answers (1)
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The number of molecules in 18cm^3 of a liquid is 6 x 10^23. Assuming that the diameter of the
molecules is equivalent to the side of...
(Solved)
The number of molecules in 18cm^3 of a liquid is 6 x 10^23. Assuming that the diameter of the
molecules is equivalent to the side of a cube having the same volume as the molecule. Determine
the diameter of the molecule.
Date posted:
September 19, 2017
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Answers (1)
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State factors affecting the spring constant of the spring
(Solved)
State factors affecting the spring constant of the spring
Date posted:
September 19, 2017
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Answers (1)
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State factors that determine the force on a current carrying conductor on the magnetic field
(Solved)
State factors that determine the force on a current carrying conductor on the magnetic field
Date posted:
September 19, 2017
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Answers (1)
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State any three characteristics of images formed by a convex mirror
(Solved)
State any three characteristics of images formed by a convex mirror
Date posted:
September 19, 2017
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Answers (1)
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State two types of curved mirrors
(Solved)
State two types of curved mirrors
Date posted:
September 19, 2017
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Answers (1)
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State any two factors the affect the stability of a body
(Solved)
State any two factors the affect the stability of a body
Date posted:
September 19, 2017
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Answers (1)
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State the basic laws of magnetism
(Solved)
State the basic laws of magnetism
Date posted:
September 19, 2017
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Answers (1)
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Name three States of equilibrium
(Solved)
Name three States of equilibrium
Date posted:
September 19, 2017
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Answers (1)
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What is the difference between longitudinal and transverse waves
(Solved)
What is the difference between longitudinal and transverse waves
Date posted:
September 19, 2017
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Answers (1)
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A copper calorimeter of mass 60g is filed with 100g of water at 250C. Steam at a normal
temperature and pressure ( N.T.P) is passed thought...
(Solved)
A copper calorimeter of mass 60g is filed with 100g of water at 250C. Steam at a normal
temperature and pressure ( N.T.P) is passed thought the water until a temperature 450C is attained.
The final mass of calorimeter and the contents was found to be 163.5g. Calculate the specific latent
heat of vaporization ‘l’ of water (Specific heat capacity for water is 4200JKg^-1 and for copper is 378Kg^-1K^1)
Date posted:
September 19, 2017
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Answers (1)
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A body moving initially at 50m/s decelerates uniformly at 2ms-2 until it comes to rest.
What distance does it cover from the time it started...
(Solved)
A body moving initially at 50m/s decelerates uniformly at 2ms-2 until it comes to rest.
What distance does it cover from the time it started to decelerate
Date posted:
September 19, 2017
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Answers (1)
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A accelerates uniformly from it initial velocity, u, the final velocity, v in time t. The distance
traveled during this time is S. If the acceleration...
(Solved)
A accelerates uniformly from it initial velocity, u, the final velocity, v in time t. The distance
traveled during this time is S. If the acceleration is denoted by the letter, a show that;
(i) V = u + at
(ii) S = ut + at2
(iii) V2 = u2 + as
Date posted:
September 19, 2017
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Answers (1)
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Equal masses of water and paraffin with specific heat capacities CW and CP respectively are heated
using identical sources of heat, for the same length of...
(Solved)
Equal masses of water and paraffin with specific heat capacities CW and CP respectively are heated
using identical sources of heat, for the same length of time. The final temperature θP of paraffin
was found to be greater than final temperature than of water, Show that CW is greater than CP.
Date posted:
September 18, 2017
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Answers (1)
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A girl heats 5 kg of water to temperature of 80oC. When she adds m kg of water at 15oC the mixture attains...
(Solved)
A girl heats 5 kg of water to temperature of 80oooC. Determine the value of m. (ignore heat changes due to the container)
Date posted:
September 18, 2017
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Answers (1)
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What characteristics of sound is applied in turning pianos
(Solved)
What characteristics of sound is applied in turning pianos
Date posted:
September 18, 2017
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Answers (1)
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What measurable quality is associated with colors of light?
(Solved)
What measurable quality is associated with colors of light?
Date posted:
September 18, 2017
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Answers (1)