For instance, the motion of a spacecraft, regarding its orbit and attitude , is described by the relativistic theory of classical mechanics, while the analogous movements of an atomic nucleus are described by quantum mechanics.
According to the NHS, the average Briton walks between 3,000 and 4,000 steps a day - significantly less than the Fitbit target. Yet many people do significantly more, and for them 10,000 steps might not be much of a target.
If you walk 10,000 steps a day, you will probably do more than 150 minutes and that's great: research suggests that the more activity you do the better, as regular exercise has many benefits. The average person walks between 3,000 and 4,000 steps per day. To find out how many steps you take each day, use a pedometer. If you have a smartphone, you may be able to download a pedometer app. Pedometers measure your every step: around the house, across the office, window shopping, to school or the park.