This week, we tackle the hirsute - will clean, trimmed hair grow quickly? Can you slow the growth with neglect? We find out if cut hair grows back quicker and thicker, or if that's just an urban myth. Also, we ask how tide times are so precise, and why people lose their accent when they sing... Like this podcast? Please help us by supporting the Naked Scientists

Our question this week concerns caves - we find out if more carbon dioxide in the atmosphere causes caves to grow quicker. Could an acidic atmosphere create cathedral-sized caverns? Like this podcast? Please help us by supporting the Naked Scientists

This week, we find out if our noses tell us the truth. Does a strong smell mean a lot of odour in the air, or can we be tricked by small smells? In short, does our sense of smell have a sense of scale? Also, we ask if more carbon dioxide in the air leads to bigger caves in the ground, and can you slow the growth of your hair by not having it cut? Like this podcast? Please help us by supporting the Naked Scientists

Books can hold stories, knowledge, ideas and memories - but what about the smell? So on this week's QotW - What gives an old book that distinctive smell? Also, we ask how we perceive the 'size' of an odour, and if there's more carbon dioxide in the atmosphere - is it leading to bigger caves? Like this podcast? Please help us by supporting the Naked Scientists

This week, we find out how Electric Eels avoid a self-shock when stunning their prey, and we ask some smelly questions; what gives an old book it's distinctive smell, and does a strong smell mean a lot of odour in the air, or do our noses play tricks on us? Like this podcast? Please help us by supporting the Naked Scientists

This week, we find out how they manufacture oxygen on the International Space Station - a technique that astronauts must be 'over the moon' about! Plus, we ask how electric eels avoid self-shocking, and what gives a well loved old book that distinctive smell? Like this podcast? Please help us by supporting the Naked Scientists

This week, we find out if an aeroplane on a treadmill could the plane still take off, and ask how air is made in space, and if electric eels suffer from self-shock syndrome... Like this podcast? Please help us by supporting the Naked Scientists

This week, we find out if a fatter cyclist free-wheels faster than a thinner cyclist, and ask if an aeroplane runway is replaced with a treadmill, can the plane still take off? Also, how is oxygen recycled on the international space station? Like this podcast? Please help us by supporting the Naked Scientists

This week we find out why boomerangs keep coming back, and ask would a plane on a treadmill still take off, and who gets to the bottom of a hill first - a freewheeling fat or thin cyclist? Like this podcast? Please help us by supporting the Naked Scientists