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प्रश्न
Give an example of a physical quantity which has a unit but no dimensions.
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उत्तर
Solid angle Ω = `A/r^2` steradian and a plane angle θ = `L/r` radian. Both are dimensionless but have units.
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संबंधित प्रश्न
A calorie is a unit of heat or energy and it equals about 4.2 J where 1J = 1 kg m2s–2. Suppose we employ a system of units in which the unit of mass equals α kg, the unit of length equals β m, the unit of time is γ s. Show that a calorie has a magnitude 4.2 α–1 β–2 γ2 in terms of the new units.
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