Q. A 0.66 kg ball is moving with a speed of 100 m/s. The associated wavelength will be (h = 6.6 × 10⁻³⁴ J s)
A) 6.6 × 10⁻³² m
B) 6.6 × 10⁻³⁴ m
C) 1.0 × 10⁻³⁵ m
D) 1.0 × 10⁻³² m
Explanation
[Solution from source] λ = h/(mv) = 6.6 × 10⁻³⁴/(0.66 × 100) = 6.6 × 10⁻³⁴/66 = 1.0 × 10⁻³⁵ m. 6.6 × 10⁻³⁴ m comes from forgetting to divide by the momentum. Answer (3).
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.