Question

A physicist calculated the wall width of half brick thickness (the brick is laid in a flat position, lengthwise called stretcher position), as (13.6 ± 0.1)cm. And one brick thickness (the brick is placed in flat position, lengthwise orthogonal to wall, called header position), as (23.6 + 0.1) cm. Calculate the difference in width of walls with uncertainity in it.

Answer 1

The difference in width of walls with uncertainty in it is

$$\Delta d=[(23.6-13.13.6)\pm(0.1+0.1)]=(10\pm0.2)\text{ cm}.$$