Articles by Kabir Firaque
Explained: What new data on SARS-CoV-2 says about Covid origin, what it doesn’t
Covid origin: Scientists on Tuesday published arguments in favour of the theory that the virus possibly infected the first humans at Wuhan’s animal market. The scientists make a strong case for their argument but the analysis does not conclusively establish their theory

Updated on Mar 23, 2023 09:33 PM IST
Kabir Firaque, New Delhi
Problematics | A password to puzzles with Jamie Lee Curtis
On December 19, 2022, I invited you to crack my password to the account where I store my puzzles. Since you did, I had to change my password for security reasons — and I used JAMIE LC for inspiration. Here are #Week30's puzzles.

Updated on Mar 20, 2023 01:44 PM IST
Problematics | Rubik’s colours and Pythagorean triples
This week's puzzles include a mischievous child, a Rubik's cube, and the Pythagorean triangle. Good luck!

Published on Mar 15, 2023 10:12 AM IST
Behind room-temp superconductivity
A paper in Nature this week by scientists from the University of Rochester, who claim that they have created a material that achieves superconductivity at room temperature, has been met with a degree of scepticism. That is because the team’s earlier work has been controversial.

Published on Mar 11, 2023 11:45 AM IST
Problematics | In the name of Einstein, match the following
Creating a full-length Einstein puzzle, I found, can be an exhausting but ultimately rewarding exercise. Here you go.

Published on Mar 06, 2023 03:54 PM IST
The weight of life: Cattle 40% of all mammals by mass, wild animals 6%
Almost 40% of mammals by mass in the world are cattle, and with India accounting for around 30% of the world’s cattle according to the US Department of Agriculture, Indian cattle should account for around 12% of the mammalian biomass in the world

Updated on Mar 02, 2023 04:59 AM IST
Kabir Firaque, New Delhi
Problematics | The price of mixing apples and oranges
It may be fine to compare apples with oranges, but you should be wary about mixing the two, except perhaps in a fruit salad. Here’s why.

Updated on Feb 28, 2023 08:45 AM IST
Problematics | Untold story about a hare and a tortoise
This week, one of the two puzzles may include some information you don’t really need. Good luck!

Published on Feb 20, 2023 01:09 PM IST
Eye in the sky: Satellites, drones... back to balloons
New Delhi As a tool for surveillance, the balloon might come across as dated in this age of satellites and drones

Updated on Feb 16, 2023 01:53 PM IST
Lithium Rush: The discovery and the difficulties
Lithium is often described as the white gold of energy storage technology; light and compact, it is the defining element in the lithium-ion batteries that drive our mobile phones, laptops and, in some cases, electric cars

Updated on Feb 15, 2023 08:12 AM IST
Kabir Firaque, New Delhi
Problematics | A gift for packing things correctly
This week’s puzzles are somewhat less challenging, but interesting nevertheless. It is, incidentally, a landmark week of sorts: the 25th in an unbroken series of puzzling weeks.

Updated on Feb 14, 2023 08:05 AM IST
Problematics | Playing cards, words and a classroom game
Have you ever created something, like a poem or a word game, only to find that someone else has created something similar? This week's puzzles are one of those.

Updated on Feb 10, 2023 09:04 AM IST
Why earthquakes happen, and how to measure them
While the difference in the magnitude between the two earthquakes is a mere 0.3, the second one is two times bigger than the first, and released 2.8 times more energy, according to an online tool hosted by the US Geological Survey

Published on Feb 07, 2023 09:39 PM IST
Problematics | More tricks to play on impressionable friends
Welcome to week 23 of Problematics! Here are this week's puzzles, admittedly not my own.

Updated on Jan 30, 2023 04:57 PM IST
Problematics | The puzzling truth about cats and dogs
For any Monday’s puzzles, please send in your solutions by noon on Friday the same week. This will also be mentioned in the footnote every week. Let's get solving!

Published on Jan 23, 2023 07:04 PM IST
A timeless debate: How long can a human live?
The death of French nun Lucile Randon, known as Sister André, at age 118 — in fact, 25 days short of her 119th birthday — has revived the perennial question: how long can a person realistically hope to live?

Updated on Jan 20, 2023 01:56 PM IST
Kabir Firaque, New Delhi
Problematics | Think of a number, repeat and recycle
This week's fare is relatively simple, although the puzzles are not exactly sitters.

Published on Jan 17, 2023 03:43 PM IST
Problematics | Watch your hands and how they move
Ignore the second hand and concern yourselves only with the hour and minute hands. Like last week’s Christmas tree puzzle, this one too comes from something I had presented to readers 30 years ago.

Published on Jan 10, 2023 03:34 PM IST
How long does it take to set up an Xmas tree?
I felt the puzzle would work better if I adapted it for readers who are three decades younger. I have changed the form of the original but retained the content.

Published on Jan 02, 2023 01:24 PM IST
Problematics | The mathematics of planning a family
Here's week 18 of Problematics.

Updated on Dec 26, 2022 03:13 PM IST
Problematics | A puzzler’s guide to matchmaking
Here's week 17 of Problematics.

Updated on Dec 20, 2022 02:40 PM IST
N-fusion: The clean energy the world needs, but may not get soon enough
For the first time, a nuclear fusion experiment has achieved ignition, generating more energy that it consumed. While there are miles to go before fusion can become the source of the world’s energy needs, the results mark a milestone in scientific terms

Updated on Dec 13, 2022 10:51 AM IST
Kabir Firaque, New Delhi
Problematics | Flight of fancy: Around the world in how many days?
When someone identifies an error in someone else’s puzzle, it is called “cooking” the puzzle. Here's a simplified adaptation for readers of Problematics!

Updated on Dec 12, 2022 05:24 PM IST
Problematics | Which game is smarter, poker or teen patti?
The Hollywood caper The Sting (1973) includes a memorable depiction of a poker game, in which a lot of cheating is going on. This too is about poker, and the rules of the game now may help you warm up for The Sting later.

Updated on Dec 06, 2022 09:07 AM IST
Can hydrogen-fuelled engines be the next big leap in aviation?
In the test on a hydrogen-driven aero engine, Rolls-Royce and easyJet appear to have overcome a crucial challenge that is often mentioned when hydrogen engines are discussed — although hydrogen is meant to be a green fuel, it is produced using electricity, and generating that electricity can involve burning of fossil fuels.

Updated on Nov 29, 2022 02:16 PM IST
Kabir Firaque, New Delhi
Problematics | How the crow flies between World Cup football fans
The football World Cup provides the ideal occasion to release a puzzle that I had so far been holding on to. It’s not about football, but involves fans of the game. And it’s not extremely difficult, but it’s fun when you figure out how to solve it.

Published on Nov 28, 2022 01:25 PM IST
Problematics | World Cup goals set on your table
The World Cup is an occasion we cannot ignore. I hope you enjoy solving the following football-related puzzles as much as I enjoyed creating them.

Updated on Nov 22, 2022 01:16 PM IST
Problematics | Play Wordle with these movie titles
Neither of this week’s puzzles is exceptionally tough, but one will require harder work than the other. That one is not mathematical, but a word puzzle that also requires some knowledge of Hollywood:

Published on Nov 15, 2022 12:24 PM IST
Problematics | The weight of a bulldog and friends
The following kind of puzzle is one involving two equations and three variables, whose values you need not determine while getting to the answers you are looking for.

Published on Nov 07, 2022 02:27 PM IST
The science behind the load, span and design of a safe bridge
Different kinds of bridges require different factors to be taken into consideration. HT explains:

Published on Nov 01, 2022 09:46 PM IST
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