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What is the speed of a particle of mass 10-27kg w...

What is the speed of a particle of mass 10-27kg whose wavelength is 10-8m.

[h = 6.63 x 10-34Js]

A.

6.63ms-1

B.

66.30ms-1

C.

663.00ms-1

D.

6630.00ms-1

Correct answer is B

Energy of a particle is given by
E = hf = hV/λ (since V = fxλ)
But in terms of mass M, E = ∆MV2
∴ ∆MV2 = hV/λ
∆MV = h/λ
∴ V = h/λ∆M
V = 6.63 x 10-34/(10-27 x 10-8)
V = 6.63 x 10-34/10-35
V = 6.63 x 10-34+35
V = 6.63 x 10
V = 66.3ms-1