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Projectile

A projectile is any object thrown into space by the exertion of a force. Although any object in motion through space may be called a projectile, the term more refers to a ranged weapon. Mathematical equations of motion are used to analyze projectile trajectory. An object projected at an angle to the horizontal has both the vertical and horizontal components of velocity; the vertical component of the velocity on the y-axis given as Vy=USin while the horizontal component of the velocity Vx=UCos. There are various terms used in projectiles at specific angle teta 1. Time to reach maximum height, it is symbolized as, the time taken for the projectile to reach the maximum height from the plane of projection. Mathematically, it is given as t=USin/g Where g=acceleration due to gravity U= initial velocity teta= angle made by the projectile with the horizontal axis. 2. Time of flight: this is the total time taken for the projectile to fall back to the same plane from which it was projected. Mathematically it is given as T=2USin/g 3.

Maximum Height: this is the maximum height attained by the projectile OR the maximum displacement on the vertical axis covered by the projectile. It is given as H= U²Sin²/2g 4. Range: The Range of a projectile is the horizontal distance covered by the projectile. Mathematically, R= U²Sin2/g; the Range is maximum when angle teta= 45° I.e Sin2=1. Blowguns and pneumatic rifles use compressed gases, while most other guns and cannons utilize expanding gases liberated by sudden chemical reactions. Light-gas guns use a combination of these mechanisms. Railguns utilize electromagnetic fields to provide a constant acceleration along the entire length of the device increasing the muzzle velocity; some projectiles provide propulsion during flight by means of a rocket jet engine. In military terminology, a rocket is unguided. Note the two meanings of "rocket": an ICBM is a guided missile with a rocket engine. An explosion, whether or not by a weapon, causes the debris to act as multiple high velocity projectiles.

An explosive weapon, or device may be designed to produce many high velocity projectiles by the break-up of its casing, these are termed fragments. Many projectiles, e.g. shells, may carry an explosive charge or another chemical or biological substance. Aside from explosive payload, a projectile can be designed to cause special damage, e.g. fire, or poisoning. In projectile motion the most important force applied to the ‘projectile’ is the propelling force, in this case the propelling forces are the muscles that act upon the ball to make it move, the stronger the force applied, the more propelling force, which means the projectile will travel farther. See pitching, bowling. A projectile that does not contain an explosive charge or any other kind of payload is termed a kinetic projectile, kinetic energy weapon, kinetic energy warhead, kinetic warhead, kinetic kill vehicle or kinetic penetrator. Typical kinetic energy weapons are blunt projectiles such as rocks and round shots, pointed ones such as arrows, somewhat pointed ones such as bullets.

Among projectiles that do not contain explosives are those launched from railguns and mass drivers, as well as kinetic energy penetrators. All of these weapons work by attaining a high muzzle velocity, or initial velocity up to, collide with their targets, converting their kinetic energy into destructive shock waves and heat. Other types of kinetic weapons are accelerated over time by gravity. In either case, it is the kinetic energy of the projectile; some kinetic weapons for targeting objects in spaceflight are anti-satellite weapons and anti-ballistic missiles. Since in order to reach an object in orbit it is necessary to attain an high velocity, their released kinetic energy alone is enough to destroy their target. For example: the energy of TNT is 4.6 MJ/kg, the energy of a kinetic kill vehicle with a closing speed of 10 km/s is 50 MJ/kg. This saves costly weight and there is no detonation to be timed; this method, requires direct contact with the target, which requires a more accurate trajectory.

Some hit-to-kill warheads are additionally equipped with an explosive directional warhead to enhance the kill probability. With regard to anti-missile weapons, the Arrow missile and MIM-104 Patriot PAC-2 have explosives, while the Kinetic Energy Interceptor, Lightweight Exo-Atmospheric Projectile, THAAD do not. A kinetic projectile can be dropped from aircraft; this is applied by replacing the explosives of a regular bomb with a non-explosive material, for a precision hit with less collateral damage. A typical bomb has a speed of impact of 800 km/h, it is applied for training the act of dropping a bomb with explosives. This method has been used in Operation Iraqi Freedom and the subsequent military operations in Iraq by mating concrete-filled training bombs with JDAM GPS guidance kits, to attack vehicles and other "soft" targets located too close to civilian structures for the use of conventional high explosive bombs. A Prompt Global Strike may use a kinetic weapon. A kinetic bombardment may involve a projectile dropped from Earth orbit.

A hypothetical kinetic weapon that travels at a significant fraction of the speed of light found in science ficti

Dedaye Bridge

Dedaye Bridge known as the Ayeyarwady-Dedaye Bridge is a bridge linking Kungyangon Township in Yangon Division and Dedaye Township in Ayeyawady Division in southern Burma. It crosses the Ayeyawady River; the construction of Dedaye Bridge across Toe River started on 10 June 2000. The bridge is equipped with RCD bole piles and steel frame, it is 4,088.3 feet long and 28 feet wide, has six-foot-wide pedestrian lanes on both sides. The clearance under the bridge is 350 feet wide; the bridge can bear 60-ton loads. Dedaye Bridge was built by Public Works of the Ministry of Construction; the Dedaye Bridge linking Yangon and Ayeyawady Divisions was opened on 23 March 2003 7.30 am as a gesture of hailing the 58th Anniversary Armed Forces Day by member of the State Peace and Development Council Lt-Gen Thura Shwe Mann. The opening ceremony of Dedaye Bridge was held at the pandal near the bridge in Kungyangon Township; the bridge with the length of over 4,000 feet is part of the Yangon-Kungyangon-Dedaye-Pyapon-Kyaiklat-Maubin-Yangon Main road.

With the use of the bridge, one can travel Pyapon-Kyunkadon-Seikma-Ahma trip, Pyapon-Bogale trip, Maubin-Nyaungdon-Pathein and Nyaungdon-Hinthada trips and Nyaungdon-Thandwe of Rakhine State trip. It was built at a cost of 1.6 million US dollars. The Dedaye Bridge was built in nine months. Lt-Gen Thura Shwe Mann and party posed for a documentary photo together with Deputy Superintending Engineer of Public Works U Khin Maung Win and officials in front of the archway. Http://www.myanmar.gov.mm/NLM-2003/enlm/mar24_rg1.html

Dreifrankenstein

The Dreifrankenstein is a boundary stone that marks the tripoint where the three Franconian provinces of Upper and Lower Franconia meet in southern Germany. As part of the regional reforms in 1972 the boundary marker was moved around 7 kilometres as the crow flies to the southeast. Today both points are marked by stones that are referred to as the New Dreifrankenstein; the Old Dreifrankenstein erected in 1892, is a 135 cm high column made of sandstone. It is located in woodland on the territory of Sandhügel, several hundred metres west of Kleinbirkach and east of Ebersbrunn near the source region of the Reiche Ebrach stream, its GPS coordinates are 49°47′32″N 10°28′01″E. The New Dreifrankenstein, laid in 1979, is a 280 cm high glacial erratic made of muschelkalk, in which the coats of arms of the three Franconian provinces have been carved, it is located on an eminence in the Steigerwald forest, southwest of Heuchelheim, northwest of Freihaslach and east of Sixtenberg. Its GPS coordinates are 49°45′21″N 10°33′04″E.

On the Dreifrankenstein is a geodetic reference point whose coordinates are 49.75565987°N 10.55110917°E / 49.75565987.