At what speed (m/s)must a 10.0-mg object be moving to have a de Broglie wavelength of 3.3 × 10^-41 m? A)4.1 B)1.9 × 10^-11 C)2.0 × 10¹² D)3.3 × 10^-42 E)1.9 × 10¹³

Question

Quizplus · Accepted Answer

The de Broglie wavelength of a particle with mass m and velocity v is given by λ=h/mv, where h is the Planck constant.
Rearranging the equation, v=h/mλ.
Plugging in the given values, we get
v=h/mλ = 6.63x10^-34 J s / (10^-11 kg x 3.3x10^-41 m) = 2.0 x 10^12 m/s.
Expressing the answer in scientific notation, we get 2.0 x 10^12 = 2.0 x 10^12 x 10^-3 = 2.0 x 10^9 m/s = 2.0 x 10^1 km/s.
Therefore, the answer is choice C.

At What Speed (M/s)must a 10