Knowledge World

Do you know how to measure mass of any planet?  How it possible? There are the many type of questions like this?  That is a very interesting topic for all of us. Everybody know Earth is the third planet from the Sun. The mass of the Earth may be determined using Newton's law of gravitation. It is given as the force (F), which is equal to the Gravitational constant multiplied by the mass of the planet and the mass of the object, divided by the square of the radius of the planet. We set this equal to the fundamental equation, force (F) equals mass (m) multiplied by acceleration (a). We know that the acceleration due to gravity is equal to 9.8 m/s2, the Gravitational constant (G) is 6.673 × 10−11 Nm2/kg2, the radius of the Earth is 6.37 × 106 m, and mass cancels out. When we rearrange the equation and plug all the numbers in, we find that the mass of the Earth is 5.96 × 1024 kg. F = Gm1m2/r2 = ma ...

Spacesuits Spacesuits allow astronauts to work outside a spacecraft in orbit, on the moon or on another planet. A spacesuit is much more than a set of clothes astronauts wear on spacewalks. A fully equipped spacesuit is really a one-person spacecraft. The formal name for the spacesuit used on the space shuttle and International Space Station is the Extravehicular Mobility Unit, or EMU. "Extravehicular" means outside of the vehicle or spacecraft. "Mobility" means that the astronaut can move around in the suit. The spacesuit protects the astronaut from the dangers of being outside in space. What Are the Parts of a Spacesuit? The spacesuit consists of several pieces. The Hard Upper Torso covers the astronaut's chest. The arm assembly covers the arms and connects to the gloves. The helmet and Extravehicular Visor Assembly are designed to protect the astronaut's head while still allowing him or her to see as much as possible. The Lower Torso Assemb...

Special Relativity Theory Special relativity is a theory proposed by Albert Einstein Eric Weisstein's World of Biography that describes the propagation of matter and light at high speeds. It was invented to explain the observed behavior of electric and magnetic fields, which it beautifully reconciles into a single so-called electromagnetic field, and also to resolve a number of paradoxes that arise when considering travel at large speeds. When Einstein applied his theory to gravitational fields, he derived the "curved space-time continuum" which depicts the dimensions of space and time as a two-dimensional surface where massive objects create valleys and dips in the surface. This aspect of relativity explained the phenomena of light bending around the sun, predicted black holes as well as the Cosmic Microwave Background Radiation (CMB) -- a discovery rendering fundamental anomalies in the classic Steady-State hypothesis. For his work on relativity, the photoelectr...

                What is space and time?   In physics, spacetime is any mathematical model that fuses the three dimensions of space and the one dimension of time into a single four-dimensional continuum. Spacetime diagrams can be used to visualize relativistic effects such as why different observers perceive where and when events occur differently. Another corollary of special relativity is that, in effect, one person’s interval of space is another person’s interval of both time and space, and one person’s interval of time is also another person’s interval of both space and time. Thus, space and time are effectively interchangeable, and fundamentally the same thing (or at least two different sides of the same coin), an effect which becomes much more noticeable at relativistic speeds approaching the speed of light. Einstein’s former mathematics professor, Hermann Minkowski, was perhaps the first to note this effect (and perhaps...