Question

The position of both, an electron and a helium atom is known within $0.1 \,nm$. Further the momentum of the electron is known within $5.0 \times 10^{-26} \,kg \, ms ^{-1}$. The minimum uncertainty in the measurement of momentum of helium atom is.

• A. $50 \, kg \,ms ^{-1}$
• B. $5.0 \times 10^{-26} \,kg \, ms ^{-1}$
• C. $80 \,kg \,ms ^{-1}$
• D. $80 \times 10^{-26} \,kg \,ms ^{-1}$

Answer 1

Answer: (B)

the product of uncertainties in the position and momentum of subatomic particle $=h / 4 \pi$
since $\Delta x$ is same for electron and helium ,so $\Delta p$ must be the same for both particles.