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Js is the unit of ________ physical quantity.

Asked in GUJCET 2024 · Units and conversions

Answer: (4) Angular momentum

Step-by-step solution

Given: the unit J s.

Idea: expand it in base units. J=N m=kg m² s⁻², so J s=kg m² s⁻¹.

That is (mass)×(length)×(length per unit time) -- exactly the combination mvr.

mvr is the angular momentum of a particle, so angular momentum is measured in J s.

Planck's constant has the same unit, which is why Bohr's condition can be written mvr=(nh)/(2π): h and angular momentum are quantities of the same kind.

So J s is the unit of angular momentum.

Why the other options are wrong

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