The Force is With You? You may have heard that gravity isn't a force. This is true. Gravity is not a force; however, this truth leaves us with a number of questions. For example, we're commonly told ...

The terms weight and mass are often used incorrectly. Phrases like ‘a bag of sugar weighs 1 kg’ are not scientifically correct. This means that a 1 kg mass would be attracted to Earth by a force of 10 ...

Gravity is the attraction between two objects that have mass or energy, whether this is seen in dropping a rock from a bridge, a planet orbiting a star or the moon causing ocean tides. Gravity is ...

Barry Lienert, a geophysicist at the University of Hawaii, provides the following explanation. We start by determining the mass of the Earth. Issac Newton's Law of Universal Gravitation tells us that ...

Figure 1: Side (a) and front (b) views of the apparatus. Because classification or localization performance for physical and virtual surfaces was equivalent, virtual surfaces can be considered as ...