New Scientist 14Mar2020

52 | New Scientist | 14 March 2020

The back pages Puzzles

Quick crossword #53 Set by Richard Smyth Quick quiz #42 Puzzle set by Colin Beveridge

#50 Crossing the river

Petal is on her way to a country fair, to sell

some vintage kitchenware belonging to

her good friend Gretel. As she walks along

the River Biddle admiring the view, Petal

trips on a pair of oars left carelessly on the

bank. A valuable wrought-iron kettle flies

out of her hand and lands on one of the

river’s many marshy islands.

From the river bank to the island is

3 metres directly across, and though the

oars are sturdy enough to walk on, they

are just short of reaching over the water.

How can Petal reach the island with

the paddles and save Gretel’s metal kettle

from its muddy peril?

Answer next week

#49 The tree in the snow globe

Solution

The tree can move 8 centimetres from the

centre. Viewed side-on, so the snow globe

appears as a semicircle, imagine moving the

tree as far as it can go. Line b, from the centre

of the base of the globe to the top of the tree,

is the radius of the semicircle: 10cm. The

height of the tree and the distance it has

moved form the other two sides of a

right-angled triangle, so we can use

Pythagoras’ theorem to find the distance.

1 What objects are classified

by position on a Hertzsprung-

Russell diagram?

2 Tarsiers, tiny primates in

South-East Asian jungles,

are notable for having

relatively enormous what?

3 Paris, Marrakesh, Bonn,

Katowice, Madrid... what city

is next in this sequence?

4 A German scholar outlined

23 great unsolved problems

of mathematics in a famous

address at the Sorbonne in

Paris in 1900. Who was he?

5 Which of his problems,

involving the distribution of

prime numbers, remained

sufficiently great and

unsolved a century later to

be one of seven “Millennium

Problems” announced by the

Clay Mathematics Institute?

Answers below

Cryptic

Crossword #26

Answers

ACROSS 1 Whoops, 4 IQ test,

9  Buffalo, 10 Aspic, 11 Algae,

13 Oak tree, 14 Jugular vein,

18  Timpani, 20 Niece, 21 Pinna,

22 Uploads, 24 Ersatz, 25 Cation

DOWN 1 Webcam,

2/17 Off season, 3 Plateau,

5  Quark, 6  Expertise, 7 Ticker,

8  Coronavirus, 12 Gourmands,

15 Vanilla, 16 Steppe,

19  Adapt,  23 Ali

Quick quiz #42

Answers

Stars, placed on two axes 1

according to their luminosity

or magnitude, and their

temperature or colour

Eyes. The only entirely 2

carnivorous primates, they are

nocturnal hunters with eyes that,

at around 1.5 cm in diameter, are

as big as their brains.

Glasgow. It will hold the 3

2020 annual UN climate

change conference

David Hilbert 4

The Riemann hypothesis 5

 



 





  



  

 

 

 

ACROSS

1 May tree (8)

5 ___ Around Us, 1951 book

by Rachel Carson (3,3)

9 Enveloped rock fragment (8)

10 Small flower (6)

11 1999 sci-fi film by

David Cronenberg (8)

12 Otzi the ___, the

Hauslabjoch mummy (6)

14 Low-growing plant in the

genus Cressa (10)

18 Formation of a

blood clot (10)

22 Move around an axis (6)

23 Extra sail on a square-

rigged ship (8)

24 Long-fingered lemur (3-3)

25 Autostereogram (5,3)

26 Data obsessive (6)

27 Crewed NASA mission

of 1970 (6,2)

Answers and the next cryptic crossword next week.

DOWN

1 Thomas Henry ___,

“Darwin’s bulldog” (6)

2 Game theory scenario in

which all participants

profit (3-3)

3 Rock salt (6)

4 Photoreceptor cell (7, 3)

6 Minimal surface described

by Euler in 1774 (8)

7 String trimmer (8)

8 Th, Pa, U or Bk, perhaps (8)

13 US geologist and oceanic

cartographer (5,5)

15 Nickname for the Strategic

Defense Initiative (4,4)

16 Redness of the skin (8)

17 Violet quartz (8)

19 Use of spare urban land (6)

20 Improvise; cope with

suboptimal conditions (4,2)

21 1992 sci-fi sequel directed

by David Fincher (5,1)

Our crosswords are

now solvable online

Available at

newscientist.com/crosswords

3 m

6 m

c = 6

b = 10

a

a^2 + b^2 = c^2