An object is placed in front of a concave lens at a distance of 45 cm from it. If its image is formed at a
distance of 30 cm from the lens, calculate the focal length of the lens.

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What is the correct energy transformation during burning of a candle?

Copper wire is wound around a steel bar FT. Current is allowed to pass through the coil for some time
and then the bar is removed.
(a) Draw only the magnetised bar FT and mark its poles.
(b) Trace two magnetic lines of force around FT clearly indicating the direction.
F T

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A body is acted upon by two equal and opposite forces, that are NOT along the same straight line. The
body will:

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Which among the following is a vector quantity?

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When a ray of light passes from one optical medium to another, which of the following physical quantities
does NOT change?

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Which one of the following combinations is the correct ascending order of electromagnetic waves in
terms of wavelength?