Why are bubbles round and when was gravity discovered? Try our kids’ quiz

1. Maya, 5, asks: why are bubbles round?

   1. Because a sphere is by far the best shape for floating

   2. Because soap has round molecules so it means that bubbles are also round

   3. Because the surface tension of liquid makes bubbles that shape

   4. Because cubes are easier to pop and would burst too quickly

2. Jay, 7, asks: when was gravity discovered?

   1. In 1666

   2. In 1921

   3. In Ancient Egyptian times

   4. In 2011

3. Emily, 9, asks: how many times a day do we blink?

   1. 300-700 times

   2. 1,000-2,000 times

   3. 15,000-20,000 times

   4. 800,000-1 million times

4. 4 Olly, 8, asks: why is the sea salty?

   1. Because of all the minerals that are dissolved in it

   2. Because in ancient times an enormous ship carrying salt ran aground and sank, and so the whole sea became salty

   3. Salt factories are usually under water, and lots of salt escapes from them and goes into the sea

   4. Because fish wee is very salty

5. Kiry, 11, asks: what is the name of the commonly seen red and white toadstool?

   1. Polka dot fungus

   2. Angel’s delight

   3. Fly agaric

   4. Fairy’s trampoline

Solutions

1:C - Bubbles are spherical because the surface tension of the liquid pulls the bubble tight. A sphere is the best possible shape to enclose the most volume with the least surface area – so that’s how they form naturally., 2:A - Gravity was supposedly discovered in 1666 by Isaac Newton when an apple fell from a tree and made him question why it fell down to the ground and not upwards or sideways. This story might just be a myth, and many other scientists have contributed to the discovery of gravity. , 3:C - We blink about 15-20 times a minute, so during the hours you’re awake, this makes up about 15,000-20,000 blinks every day! , 4:A - Rainwater washes minerals containing salts from the land into rivers. Over millions of years, rivers flowing into the sea have carried these dissolved salts from the land into the ocean. About 3.5% of the weight of seawater comes from the salts dissolved in the water., 5:C - The fly agaric (Latin name: Amanita muscaria) was given its name because it can be used to attract and kill flies.

Scores

1. 5 and above.

2. 4 and above.

3. 3 and above.

4. 2 and above.

5. 0 and above.

6. 1 and above.

Molly Oldfield hosts Everything Under the Sun, a weekly podcast answering children’s questions, out now as a book.

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