Table-tennis ball has mass 10 g and speed of 90 m/s. If speed can be measured within an accuracy of 4%, what will be the uncertainty in speed and position?


Given that, speed=90 m/s
mass=10g=10×10-3kg
Uncertainty in speed (v)=4%of90ms-1=40×90100=3.6ms-1
From Heisenberg uncertainty principle,
x·v=h4πm
or x=h4πmv
Uncertainty in position,
x=6.626×10-34kgm2s-14×3.14×10×10-3kg×3.6ms-1
=1.46×10-33m