2020-03-14_New_Scientist

(Grace) #1

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
Free download pdf