Question

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

Answer 1

Given, mass of ball = 10g = 10* 10^-3 kg

speed = 90m/s

accuracy = 4%

so uncertainty in speed = 4% of 90 = 4*90/100 = 3.6 m/s

so using uncertainty formula

$\Delta x * \Delta v = h/4\pi m$

$\Delta x= 6.626*10^{-34}/(4*3.14*10^{-2}*3.6)$

$\Delta x = 1.46 * 10 ^{-33}$ m