A log of wood cut by a saw becomes hot. From where does this heat energy come?
[2] Work, Energy and Power
Chapter: [2] Work, Energy and Power
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Our hands become warm when we rub them against each other. Why?
[2] Work, Energy and Power
Chapter: [2] Work, Energy and Power
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The head of a nail becomes warm when it is hammered into a plank of wood. Explain the series of energy transformation taking place in the process.
[2] Work, Energy and Power
Chapter: [2] Work, Energy and Power
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What is meant by a centripetal force? Is it same as centrifugal force?
[1] Force
Chapter: [1] Force
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The following are some of the energy transformations.
A. Electrical to light
B. Work to heat
C. Chemical to light
D. Electrical to sound
E. Mechanical to electrical
Identify the energy transformation that takes place in the following by inserting the corresponding letter in the shape provided.
(i) A candle flame
(ii) A torch is lighted
(iii) A microphone is used in a meeting
(iv) A cycle dynamo
(v) A piece of metal is being filed
[2] Work, Energy and Power
Chapter: [2] Work, Energy and Power
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Identify the type of energy possessed by the body in the following:
A coiled spring of the toy car.
[2] Work, Energy and Power
Chapter: [2] Work, Energy and Power
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Name the phenomenon which enables an empty test tube placed inside water shine like a mirror.
[4] Refraction of Light at Plane Surfaces
Chapter: [4] Refraction of Light at Plane Surfaces
Concept: undefined >> undefined
Plot a graph between
Angle of incidence versus angle of reflection,
[4] Refraction of Light at Plane Surfaces
Chapter: [4] Refraction of Light at Plane Surfaces
Concept: undefined >> undefined
Plot a graph between
Sine of angle of incidence versus sine of angle of refraction,
[4] Refraction of Light at Plane Surfaces
Chapter: [4] Refraction of Light at Plane Surfaces
Concept: undefined >> undefined
Plot a graph between
Angle of incidence versus angle of refraction.
[4] Refraction of Light at Plane Surfaces
Chapter: [4] Refraction of Light at Plane Surfaces
Concept: undefined >> undefined
If a light ray does not undergo, refraction at the boundary between two media, the angle of incidence is:
[4] Refraction of Light at Plane Surfaces
Chapter: [4] Refraction of Light at Plane Surfaces
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State two factors which affect the critical angle for a given pair of media.
[4] Refraction of Light at Plane Surfaces
Chapter: [4] Refraction of Light at Plane Surfaces
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Define the terms critical angle and total internal reflection. State two conditions necessary for total internal reflection to occur. Write down the relation for the critical angle in terms of refractive index.
[4] Refraction of Light at Plane Surfaces
Chapter: [4] Refraction of Light at Plane Surfaces
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What do you mean by the statement 'the critical angle for diamond is 240'?
[4] Refraction of Light at Plane Surfaces
Chapter: [4] Refraction of Light at Plane Surfaces
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Define critical angle and explain total internal reflection. What are the conditions necessary for total internal reflection?
[4] Refraction of Light at Plane Surfaces
Chapter: [4] Refraction of Light at Plane Surfaces
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(a) A ray of monochromatic light enters glass PQRS as shown in the fig. Complete the path of ray till it emerges from the glass. (Critical angle of glass is 420).
(b) Draw diagram of a prism periscope.
(c) What are the advantages of total internal reflecting prism over plane mirror?
[4] Refraction of Light at Plane Surfaces
Chapter: [4] Refraction of Light at Plane Surfaces
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Make the correct choices for each of the following :
Total Internal reflection takes place when
(where ∠i = angle of incidence, ∠r = angle of refraction, ∠C = critical angle)
[4] Refraction of Light at Plane Surfaces
Chapter: [4] Refraction of Light at Plane Surfaces
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Define the term intensity of a sound wave.
[7] Sound
Chapter: [7] Sound
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State three factors on which loudness of sound heard by a listener depends.
[7] Sound
Chapter: [7] Sound
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What is the equivalent resistance of 5 equal resistors, each of value 2`Omega` 1 when oonnected in (a) Series ( b) ParaIleI?
[8] Current Electricity
Chapter: [8] Current Electricity
Concept: undefined >> undefined
