Kite

A kite is traditionally a tethered heavier-than-air craft with wing surfaces that react against the air to create lift and drag. A kite consists of wings, tethers and anchors. Kites have a bridle to guide the face of the kite at the correct angle so the wind can lift it. A kite may have fixed or moving anchors.

The lift that sustains the kite in flight is generated when air flows around the kite's surface, producing low pressure above and high pressure below the wings. The interaction with the wind also generates horizontal drag along the direction of the wind. The resultant force vector from the lift and drag force components is opposed by the tension of one or more of the lines or tethers to which the kite is attached. The anchor point of the kite line may be static or moving (e.g., the towing of a kite by a running person, boat, free-falling anchors as in paragliders and fugitive parakites or vehicle).

The same principles of fluid flow apply in liquids and kites are also used under water.

Kite (geometry)

In Euclidean geometry, a kite is a quadrilateral whose four sides can be grouped into two pairs of equal-length sides that are adjacent to each other. In contrast, a parallelogram also has two pairs of equal-length sides, but they are opposite to each other rather than adjacent. Kite quadrilaterals are named for the wind-blown, flying kites, which often have this shape and which are in turn named for a bird. Kites are also known as deltoids, but the word "deltoid" may also refer to a deltoid curve, an unrelated geometric object.

A kite, as defined above, may be either convex or concave, but the word "kite" is often restricted to the convex variety. A concave kite is sometimes called a "dart" or "arrowhead", and is a type of pseudotriangle.

Special cases

If all four sides of a kite have the same length (that is, if the kite is equilateral), it must be a rhombus.

If a kite is equiangular, meaning that all four of its angles are equal, then it must also be equilateral and thus a square. A kite with three equal 108° angles and one 36° angle forms the convex hull of the lute of Pythagoras.

Stefanie Sun

Sng Ee Tze (born 23 July 1978), better known as Stefanie Sun, Sun Yanzi, and known to fans as 13姐 ("13th sister"), is a singer-songwriter. She is known as the Singaporean Mandopop queen. She has sold over 30 million copies of her albums during the span of her career thus far. She is based in Taiwan, as she does the majority of her recordings there. Her popularity extends to China, Hong Kong, Malaysia, and her native Singapore.

Biography

Sun has an older sister three years her senior Sng Yee-kia (孙燕佳), and a younger sister six years her junior named Sng Ee-mei (孙燕美).

Sun was educated at Nanyang Primary School, St. Margaret's Secondary School, Raffles Girls' School and went on to attend Saint Andrew's Junior College. She later attended Nanyang Technological University, where she obtained a degree in Marketing, and was said to stay at Hall 6 where she was known for her singing talent. Her voice talent was discovered by her music teacher Lee Wei Song.

In the Mandarin-speaking world, Sun is more popularly known by her Mandarin name, Sun Yan-zi or Sun Yanzi. Sun has sold over 10 million copies in Asia. With eleven albums to her name, she is arguably the most successful singer from Singapore. Sun is also known to be good friends with fellow Pop Princess of Taiwan, Jolin Tsai. They are often performing guests at each other's concerts.