How Well Do You Know the World?


By: Zoe Samuel

6 Min Quiz

Image: shutterstock

About This Quiz

Planet Earth has been humanity's home throughout all of our evolution, and will be for the foreseeable future - but until the last 100 years and the commercialization of air travel, most of us really didn't see a lot of it. We had priests or ancient superstitions to tell us how it worked, and that was good enough for a farmer or a nomad living in earlier times.

These days, with the internet and easy and affordable travel for millions, not knowing what's going on with our surroundings is more of a choice than an unavoidable consequence of one's circumstances - and that means many of us have stepped up to find out the facts. 

From schools to documentaries to books to simply speaking with the smartest people we know, we have plenty of ways to find out the basics about this blue-and-white marble we call home. We can easily find out with a few clicks how big the earth is, how fast it's moving, and what's going on in its seas, skies, and continents. So let's put some questions to you about all of these fabulous facts, and see how well you really know the only planet on which most of us will ever step foot.

What is the circumference of the world?

The Earth is 24,901 miles around, or 40,075km.


What is the tallest mountain in North America?

Denali was known for a while as Mount McKinley, but returned to its old Native American name. It is the tallest mountain on the North American continent.


How many people live in the world?

World population is now 7.6 billion but growth rates are flattening as education has led women to have more opportunities and thus more chance to decide how many children they have. The result has been smaller families. If current trends continue, the world population is likely to flatten out around 11 billion.


Which country has the highest total carbon footprint?

The highest carbon footprint comes from China since it a massive population whose wealth is growing rapidly, and also because many western nations have effectively outsourced their carbon footprints by sending manufacturing there. This has resulted in horrific pollution issues, like soot particulate in the air, which kill millions of people across Asia every year as well as putting off investment in the economy. China has canceled all plans for new coal plants and just invested the better part of half a trillion dollars to go renewable, and leads the way in solar. It is also banning all cars with internal combustion engines in favor of carbon-neutral electric cars.


How many countries are in the world?

There are 195 countries in the world, 193 which are members of the United Nations.


How much has global warming already warmed the world above baseline pre-Industrial temperature?

Global warming has already added about 1.1C of warming. The level at which island nations will go under the seas, freshwater sources will be destroyed, and serious irreversible damage will occur is generally held to be about 2C, with anything over 6C meaning runaway warming beyond even that point, up to 300 feet of sea level rise, and mass extinction, possibly of humans. Fortunately, technology is changing very fast and current "business as usual" scenarios point to about 3.5C of rise. This is great news unless you live in an island nation. Scenarios for maintaining the threshold at 2C remain plausible but depend on human behavior over the next 50 years.


By biomass, what is the most abundant life form in the world?

There are an estimated 500 trillion (!) ants in the world, meaning they outweigh our 7 billion humans.


How much of the world is covered by water?

The world is currently 71 percent water. This number may go up if sea levels rise, or go down if some sort of incident like an asteroid strike causes a lot of water to evaporate or temperatures to drop and lead to a very substantial freezing.


What is the longest river in the world?

As well as being wider than the Nile, It's been proven that the Amazon is longer too, at 6992km.


What is the deepest lake in the world?

Lake Baikal is 5,387 feet deep and is a UNESCO protected site.


What is the tallest bridge in the world?

This bridge is in the South of France and spans the Tarn River Valley. It's over 1,100 feet tall and sometimes has so much mist under it that you cannot see the ground.


What is the most densely populated country in the world?

At 1,114 people per square mile, Bangladesh is the most densely populated country with a big population. It is followed by South Korea, Netherlands, and Rwanda.


What is the newest sovereign state?

South Sudan became a separate country at the end of a very bloody and long civil war. It remains a very poor country and certainly has a ways to go, but it's here, and as of 2011, it's independent!


What is the oldest continuous democracy?

While all the nations suggested as answers here have an extremely legitimate claim, Britain's democracy is the oldest one around that currently resembles representative republican democracy as we know it and hasn't been interrupted by a period of junta rule or other tyranny.


Which is the highest country in the world by average latitude?

Bhutan is the highest country in the world, though it does not contain the highest peak. It is on the Tibetan Plateau and has an average altitude of 10,761 feet.


How many countries are there in South America?

There are 15 countries of which 12 are independent states and three are dependent territories.


How many countries are there in Africa?

The AU and the UN both agree there are 54 countries in Africa. This number does change from time to time, most recently with South Sudan becoming independent in 2011.


Which country has the highest population?

China's population of 1.379 billion is the largest in the world. India is second, and the USA is a distant third.


Which country has the highest carbon footprint per person?

Despite abundant solar energy and new solar farms that make the cheapest electricity in the history of the world, most of the really bad offenders in this area are Middle Eastern petrostates, with Qatar leading the way as the worst per-person offender. This makes sense since these are places where you can get oil by sticking a straw in the ground. However, some forward-looking leaders in the area are starting to diversify their economies beyond oil.


How many continents are there?

Some say there are six continents, but that's if you count Europe and Asia together since they are one landmass. Generally, most scientists say there are seven continents.


What is the deepest point in the ocean?

The Mariana Trench is 35,462 feet deep, which means you could fit Mount Everest in it with several thousand feet to spare!


What is the lowest place on earth that is still on land?

The Dead Sea is the saltiest sea and also the lowest. Due to topography that means it's surrounded by miles and miles of mountains and high ground, it is very low without filling up with water.


Which desert has a point that is the furthest from the ocean of all land?

This point in the Gurbantünggüt Desert is 1,600 miles from the ocean, the furthest inland it is possible to go.


Which nation owns Antarctica?

Technically, seven nations own Antarctica and have overlapping claims on it, meaning no one nation really owns it. However, since you can't really build there and it's dark half the year, no one has ever had a war about it.


Who owns the oceans?

While territorial waters do extend a couple miles off a country's coastline (assuming there isn't another country within that distance), technically no one owns the ocean. This is a source of much contention since it means that people treat it like a garbage pit, no one looks after the fish, coral, and other habitats in parts of it, and whoever had the best navy generally dominated it. New treaties and policies are set to protect the oceans better in the future, modeled after successful anti-pirate treaties.


Which countries lie at the extreme ends of the old Silk Road?

The Silk Road was a trade route of the Middle Ages that connected East and West. Parts of it are now World Heritage Sites.


How many member states are currently in the EU?

Since Croatia joined in 2013, the number has been 28. Britain is going to leave in 2019 unless there is another referendum.


Which city in China was formerly part of the British Empire?

Hong Kong was on a 99-year lease and returned to China in 1997, a peaceful transfer of power. It remains the world financial center it became under the British.


How much of the world did the British Empire cover?

At its height, the Empire covered 24 percent of the planet and was so vast that the sun never set on it.


What are the permanently inhabited US overseas territories?

These five territories are permanently inhabited. Some are interested in statehood, which would mean getting representation in Congress.


What is the hottest place on earth?

Climate change hasn't changed the answer to this yet, but it looks like it will soon, with Kuwait and parts of Iran looking set to take the crown.


What is the hottest temperature ever recorded on the surface of the Earth?

This temperature was set in June 2017. While hotter temperatures are claimed, this one is the most reliable ever recorded.


How fast does the Earth move around the sun?

The Earth moves at 67,000 mph, but thanks to its spin and gravity, you don't feel it at all!


How thick is the atmosphere?

Air pressure declines dramatically as you go up from the surface, and the vast majority of air is under 10 miles away from the surface of the planet. However, you're not technically in space until you are 300 miles up.


What is generally considered to be the worst case scenario for sea level rise by the year 2100, if we continue to burn fossil fuels and emissions neither flatline nor decline?

Yes, that's right. If we continue burning fossil fuels and emission levels continue to go up, we could cause a fatal collapse in the West Antarctican ice sheet that would mean a 12-foot rise in sea levels within the lifetime of children already born. Fortunately, this is very unlikely even if we did burn all that oil, gas, and coal. However, we have probably locked in a 1- 3-foot rise from current emissions, so it's good news that emissions levels are already stalling and look set to be in decline by 2025 as carbon neutral energy achieves market incumbency.


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