The AnswerBank Articles

Can it really be too cold to snow

A. This is a common expression that, although theoretically incorrect, is in practice true. Q. Why theoretically incorrect A. Because it isn't temperature alone that determines whether snow00:00 Mon 19th Nov 2001

Why are golf balls covered in dimples

A. It's all down to aerodynamics. The dimples help reduce the drag that previously smooth golf balls experienced on their way through the air. And since a hole in one is the ultimate goal for the00:00 Mon 19th Nov 2001

How do flies manage to appear to defy gravity and walk upside down

A. The fly can stroll along our ceilings by virtue of its sticky feet. Two flaps of membrane, called pulvilli, cover their feet and allow them to cling to any surface. The combination of the hairs00:00 Mon 12th Nov 2001

Why does hot water freeze faster than cold

A. This scientific conundrum has been debated since Aristotle’s time and still continues to cause dissent among experts. Hot water, which has to loose its heat before it can freeze, shouldn't00:00 Mon 12th Nov 2001

Why should red wine but not white be allowed to breathe

A. Because red wine contains the grapes pips and skins, along with the juice. The flavour of red wine is dependent on the reaction of the tannin in these extra elements with oxygen. However the00:00 Mon 12th Nov 2001

Why does my hair always stop growing once it gets to a certain length

A. The maximum length your hair can grow is determined by your genetic make up, so I'm afraid there is little you can do about it. Hair grows in a cycle, which is divided into three stages: the00:00 Mon 05th Nov 2001

How can sailboats travel faster than the wind

A. As the boat moves in response to the apparent wind it creates its own additional wind or ‘slipstream’ that adds to the propelling forces. As long as the sailors know how to fix the sail00:00 Mon 05th Nov 2001

What does chlorine kill

A. A large number of water borne disease such as typhoid fever, dysentery, cholera and Legionnaires' disease. Q. Can't anything else be used A. Chlorine and chlorine-based compounds are the00:00 Mon 05th Nov 2001

Why are spaceships launched vertically, as opposed to along a runway like an airplane

A. Both airplanes and spaceships need lift to get them off the ground but they achieve this in different ways, which accounts for their different launch positions. An airplane uses its wings for00:00 Mon 29th Oct 2001

How is coffee decaffeinated

A. There are several methods around: extraction using organic chemicals, carbon dioxide and water processing. Q. How does organic solvent extraction work A. This was one of the early methods of00:00 Mon 29th Oct 2001

Why does tapping the top of a shaken can stop the contents from spraying everywhere

A. The tapping creates a vibration that releases the carbon dioxide bubbles from the sides and bottom of the can and they rise to the top. Here they join up, either forming bigger bubbles or mixing00:00 Mon 29th Oct 2001

How are seedless grapes grown

A. Given that seeds are the basis for propagation where seedless grapes come from appears to be quite puzzling. However most fruits, apart from citrus fruits are no longer grown from seeds anymore,00:00 Mon 22nd Oct 2001

How do water softeners work

A. They all work along the same basic principle, replacing unwanted minerals in the water with more acceptable ones: the process is called ion exchange. Generally calcium and magnesium ions are00:00 Mon 22nd Oct 2001

When will the millennium bridge work

A. The Millennium Bridge, the pedestrian bridge linking the north and south side of the Thames, was opened last year. However it had to be closed almost instantly because when people walked on it,00:00 Mon 22nd Oct 2001

How do cruise missiles work

A. Cruise missiles are guided weapons. They look like small planes and fly like normal aircraft for much of their flight, but without a pilot. Q. If no one is piloting them, how are they00:00 Mon 15th Oct 2001

Why doesn't superglue stick to the tube

A. The tube contains lots of oxygen, which prevents the glue sticking to anything while it's inside the tube. Once squeezed into the atmosphere, the contact with moisture in the air activates the00:00 Mon 15th Oct 2001

How does anthrax spread

A. Anthrax is a bacteria caused by the organism Bacillus anthracis, which can be found in cattle or other hoofed animals. The bacterium forms spores that can infect humans in three different ways:00:00 Mon 15th Oct 2001

How can deep-sea creatures bodies withstand such huge pressures

A. As SuperBunny replies the answer lies in the water itself. Most deep-sea creatures have jelly-like skin, rather than anything rigid, that consists mainly of water and cannot be crushed,00:00 Mon 08th Oct 2001

How can dental records be used to identify dead bodies when they don t know who the dead person is

A. When a body needs identifying details of its teeth are published in professional magazines. The idea is that the detailed description of decay, dental work and crowns will jog a dentist's memory00:00 Mon 08th Oct 2001

How is the lettering put into a stick of rock

A. A stick of rock with, normally red, lettering, usually spelling the seaside town where its bought, is synonymous with the Great British holiday. Each letter is made separately, starting with a00:00 Mon 08th Oct 2001