technoquest

Q Sunlight seems to be more powerful and more capable of burning human skin in the past 20 years. Have specific dangerous wavelengths in the spectrum increased in intensity recently?

A If the energy output of the sun increased, there would be no reason for all wavelengths not to increase to the same extent. It is therefore unlikely that some wavelengths have increased in intensity more than others. The higher incidence of skin cancer is more likely to be caused by our changing social habits: we sunbathe more than we did and go on holiday to sunny countries. Although the protective ozone layer in the earth's atmosphere is getting thinner as a result of pollution from CFC gases, the "holes" have been found only over Antarctica (and to a lesser extent the Arctic) and there is no evidence as yet linking the thinning over temperate latitudes with the increased incidence of skin cancer.

Q Why do some cars have a static build-up and others don't?

A It is thought to have something to do with the carbon content of the car tyres. Tyres with high carbon content are more likely to dissipate static electricity.

Q Why is nitrogen used in so many explosive materials if it is so inert?

A Nitrogen gas is inert because there are three bonds holding together only two molecules. If you like, it doesn't have any hands free. In explosives, the nitrogen atoms are held to other atoms quite loosely and can therefore form other bonds readily. This makes them an unstable material.

Q Who discovered black holes?

A Pierre Laplace, the 18th-century French philosopher, first suggested the existence of a gravity field so strong that light could not escape. Albert Einstein did the mathematics and John Wheeler coined the term "black hole". As yet there is no absolute proof that a black hole exists, although there is very strong evidence suggesting it does.

Q Why isn't there a cure for the common cold?

A The common cold is caused by many different viruses. At the moment we have few medicines to treat virus infections. Those which do exist are far too strong (and have potentially unpleasant side-effects) to risk using them just to get rid of a cold. There is no vaccine for the common cold because so many different viruses cause it and it is impossible to cope with them all. A cold makes you feel a bit grotty for a few days and then you can fight it off without treatment. So a "cure" isn't really needed.

Q How do bees navigate?

A Bees navigate using the position of the sun in relation to their journey. This information is conveyed to other members of the hive through a dance that the bees do.

These questions and answers are provided by Science Line. You can use its Dial-A-Scientist service on 0345 600444

CHRISTOPHER RILEY

PROMOTED VIDEO
Voices
Ukip leader Nigel Farage arrives at the Rochester by-election count
voicesIs it any wonder that Thornberry, Miliband, and Cameron have no idea about ordinary everyday life?
Life and Style
tech
News
i100BBC political editor Nick Robinson had a lot of explaining to do
Life and Style
Nappies could have advice on them to encourage mothers and fathers to talk to their babies more often
newsTalking to babies can improve their language and vocabulary skills
News
ebooksNow available in paperback
Latest stories from i100
Have you tried new the Independent Digital Edition apps?
Independent Dating
and  

By clicking 'Search' you
are agreeing to our
Terms of Use.

iJobs Job Widget
iJobs General

Recruitment Genius: Female Support Workers / Carers - From £8.00 per hour

£8 - £12 per hour: Recruitment Genius: To assist a young family with the care ...

Recruitment Genius: Customer Service Executive

£20000 per annum: Recruitment Genius: A Customer Service Executive is required...

Argyll Scott International: Commercial Finance Manager

£55000 - £70000 per annum: Argyll Scott International: My client, a world lead...

Argyll Scott International: Commercial Finance Manager

Negotiable: Argyll Scott International: My client, a world leading services pr...

Day In a Page

US immigration: President Obama ready to press ahead with long-promised plan to overhaul 'broken system' - but will it get past a Republican-controlled Congress?

Immigration: Obama's final frontier

The President is ready to press ahead with the long-promised plan to overhaul America's 'broken system' - but will it get past a Republican-controlled Congress?
Bill Cosby rape allegations explained: Why are these allegations coming out now? Why didn’t these women come forward earlier? And why has nobody taken legal action?

Bill Cosby rape allegations explained

Why are these allegations coming out now? Why has nobody taken legal action? And what happens next for the man once thought of as 'America's Dad'
Four years of excruciating seizures caused by the 1cm tapeworm found burrowing through a man's brain

You know that headache you’ve got?

Four years of excruciating seizures caused by the 1cm tapeworm found burrowing through a man's brain
Travelling to work by scooter is faster than walking and less sweaty than cycling, so why aren’t we all doing it?

Scoot commute

Travelling to work by scooter is faster than walking and less sweaty than cycling, so why aren’t we all doing it?
Paul Robeson: The story of how an American icon was driven to death to be told in film

The Paul Robeson story

How an American icon was driven to death to be told in film
10 best satellite navigation systems

Never get lost again: 10 best satellite navigation systems

Keep your vehicle going in the right direction with a clever device
Paul Scholes column: England must learn to keep possession and dictate games before they are exposed by the likes of Germany and Brazil

Paul Scholes column

England must learn to keep possession and dictate games before they are exposed by the likes of Germany and Brazil
Michael Dawson: I’ll thank Spurs after we win says defender as he prepares to return with Hull

Michael Dawson: I’ll thank Spurs after we win

Hull defender faces his struggling former club on Sunday ready to show what they are missing. But he says he will always be grateful to Tottenham
Frank Warren column: Dr Wu has big plans for the professionals yet he should stick to the amateur game

Frank Warren column

Dr Wu has big plans for the professionals yet he should stick to the amateur game
Synagogue attack: Fear unites both sides of Jerusalem as minister warns restoring quiet could take 'months'

Terror unites Jerusalem after synagogue attack

Rising violence and increased police patrols have left residents of all faiths looking over their shoulders
Medecins sans Frontieres: The Ebola crisis has them in the headlines, but their work goes far beyond West Africa

'How do you carry on? You have to...'

The Ebola crisis has Medecins sans Frontieres in the headlines, but their work goes far beyond West Africa
Isis extends its deadly reach with suicide bombing in Kurdish capital

Isis extends its deadly reach with suicide bombing in Kurdish capital

Residents in what was Iraq’s safest city fear an increase in jihadist attacks, reports Patrick Cockburn
Underwater photography competition winners 2014 - in pictures

'Mysterious and inviting' shot of diver wins photography competition

Stunning image of cenote in Mexico takes top prize
Sir John Major: Negative West End portrayals of politicians put people off voting

Sir John Major hits out at theatres

Negative West End portrayals of politicians put people off voting
Kicking Barbie's butt: How the growth of 3D printing enabled me to make an army of custom-made figurines

Kicking Barbie's butt

How the growth of 3D printing enabled toy-designer to make an army of custom-made figurines