Puzzle for Today
Puzzle No. 501 鈥� Thursday 13 June
It is the one hundredth anniversary of the observation which proved Einstein was right about relativity (/news/science-environment-48369980) so some engineering students have built a machine in which they can travel close to the speed of light. When they travel, time for them passes 40% slower than for people on Earth. Their friends are hosting a May Week party on the 14th of June but they decide it would be appropriate to set off in their machine and arrive at the party on the 31st of May, two weeks early. When should they set off?
Today’s #PuzzleForToday has been set by Dr Shaun Fitzgerald, Director of The Royal Institution
Click here for the answer
If the students travel for 5 weeks in earth time, they only experience a travel time of 5 x 60% = 3 weeks. Therefore, when they return they are 2 weeks behind everyone else on earth. Mission accomplished by setting off on 10 May.
-
![]()
Puzzle for Today 鈥� Index
Find all of the currently available Puzzles for Today, with answers.
More fiendish brain-teasers and quizzes on 成人快手 Radio...
-
![]()
From autumn leaves to the magic roundabout: test yourself with our favourite quizzes.
-
![]()
We asked the intelligence agency to set our listeners a code-cracking challenge... Can you solve it?
-
![]()
Quiz: How many of these Mastermind music questions can you answer?
Here's a chance to find out whether your specialist subject on Mastermind could be the entire history of music.
-
![]()
Six conundrums to grapple with, including the Riddle of the Sphinx. Try not to forfeit your life...
