- Lightning never strikes the same place twice
This couldn’t be further from the truth. It's likely a figure of speech that gradually became accepted as fact. Lightning frequently strikes the same spot repeatedly. Tall structures such as skyscrapers and towers can be struck dozens of times per year. Lightning tends to strike the same places repeatedly, especially if those places are tall, isolated, conductive and located in areas prone to thunderstorms. A lightning bolt doesn't "remember" where it struck before. Each strike is determined by atmospheric conditions at that moment. Once a path to the ground is established, subsequent strikes may even follow a similar route. While rare, there are documented cases of people being struck by lightning more than once, particularly those who work outdoors such as park rangers, farmers, and meteorologists. One famous example is Roy Sullivan, a U.S. park ranger who is reported to have survived seven lightning strikes over his lifetime, earning a place in record books.
- Water conducts electricity
This is only half true. Pure distilled water is actually a poor electrical conductor. It's the dissolved minerals and impurities in most real-world water that carry electrical current. Distilled water is a poor conductor. If you had laboratory-grade distilled water and placed two electrodes in it, very little current would flow. However, if you added just a small amount of salt, the conductivity would increase dramatically because the salt dissolves into charged ions. Seawater is an excellent conductor. Tap water with its impurities is a moderate conductor. WARNING - So unless you are testing with pure lab-grade distilled water then your bath water and electricity are not a good mix. In practical situations, water often provides a good path for electricity. Do not use your hair drier in the bath!!
- Humans evolved from modern monkeys
Neither evolved from the other. Humans, monkeys, apes, and other primates share common ancestors. Modern humans did not evolve from the monkeys alive today. Instead, humans and modern monkeys descended from earlier primates that lived millions of years ago. Humans and monkeys share ancient ancestors without one evolving directly from the other. For info chimpanzees and bonobos are our closest living relatives.
- A penny dropped from a skyscraper can kill someone
It sounds reasonable because we learn that gravity constantly accelerates falling objects. However due to air resistance, a penny, due to being very light, flat and small reaches a relatively low terminal velocity. They tend to tumble, spin and wobble on their journey down making them even less efficient as a killing machine as they fall. It might hurt, but it is highly unlikely to be fatal.
- Hair and fingernails continue growing after death
You'll often hear this in horror stories, crime dramas, and urban legends. Growth stops at death. Growth requires living cells, nutrients, oxygen, hormones, and energy. Once circulation and metabolism stop, the cells responsible for producing new hair and nail tissue stop functioning as well.
Its less spooky but the appearance of growth is an illusion caused by the skin shrinking as the body dehydrates. This myth may persist due to hair and nails being among the last body structures to visibly decompose along with a good dose of folklore.
- You lose most body heat through your head
Heat loss depends on which body parts are exposed. The head loses no more heat proportionally than other uncovered areas. The head is not fundamentally different from the rest of your body when it comes to heat loss. Your head loses heat at roughly the same rate per unit area as other exposed skin.
Don’t throw away your hat though! - Preventing heat loss from any exposed area helps maintain body temperature and keeps you warm.
- Cold weather causes colds
Viruses cause colds; cold weather may help transmission but is not the direct cause. You cannot catch a cold simply from being cold. The common cold is most often caused by rhinoviruses and several other respiratory viruses. To develop a cold, you generally need to be infected by a virus, usually through breathing in virus-containing droplets, touching contaminated surfaces and then your nose, mouth, or eyes, close contact with an infected person. Without exposure to a virus, cold weather alone won't give you a cold.
So why do I get colds in the winter? (I hear you ask). Well… People spend more time indoors in poorly ventilated spaces, some viruses survive better in cold, dry air. Your respiratory defences may work less effectively. So - Viruses cause colds, and winter conditions help those viruses spread more effectively.
- Humans have five senses
I blame Aristotle, who identified the five primary senses we all know. We actually have many more, including balance, temperature, pain, and body-position sensing, internal body awareness. Some scientists include itch sensation, sense of time, bladder fullness and muscle tension.
- A swan can easily break your arm with a flap of its wing
Parents and grandparents have repeated this warning for generations. Swans can certainly hurt and intimidate people, but breaking a healthy adult's arm is extraordinarily unlikely and widely regarded as a myth. They can be highly territorial, especially during nesting season. A defensive swan may hiss, peck, chase, or strike with its wings and people can suffer bruises, scratches, or be knocked off balance.
