New Scientist - USA (2019-10-12)

52 | New Scientist | 12 October 2019

The back pages Puzzles

Cryptic crossword #16 set by Sparticle Quick quiz #24 Puzzle set by Ben Sparks

#25 Car crash maths

Two cars of the same model, one blue,

one yellow, are on a motorway in the UK.

The blue car is in the inside lane travelling

at 70 miles per hour*, which is the speed

limit. The yellow one is speeding in the

outside lane at 100mph.

At the instant when they are neck and

neck, both drivers see a fallen tree across

the road some distance ahead. Both

immediately brake, each applying the

same constant braking force. The blue

car manages to stop centimetres short of

the tree. To the nearest 10mph, at what

speed does the yellow car hit the tree?

a) 10mph

b) 30mph

c) 50mph

d) 70mph

Use your intuition (particularly if you

are a driver) to have a guess. Then work

out the answer to see if you were right.

* Alternatively, call the starting speeds

70 kilometres per hour and 100km/h, the

number in the solution will be the same.

Answer next week

#24 Three stamps

Solution

a) To allow all postage values up to

15 cents using no more than three

stamps, the choice of 1¢ and 5¢ stamps

is obvious. That leaves the values 4, 8, 9,

12, 13 and 14 unaccounted for, which

can be solved by choosing 4¢ as the third

stamp. So you need to choose 1¢, 4¢

and 5¢ stamps.

b) To make all postage values to 24¢

with four stamps or less, choosing 1¢,

4¢ and 8¢ stamps is sensible. To cover

the values not possible with those, the

fourth stamp must be 7¢.

1 What name is given to the

sudden appearance of most

animal lineages in the fossil

record starting around

541 million years ago?

2 Soft body parts fossilised

in which rock formation in

the Canadian Rockies are

crucial to understanding that

sudden shift in life on Earth?

3 Which US palaeontologist

and science populariser’s

1989 book Wonderful Life

brought those Canadian

fossils to wider attention?

4 What name, referring

to their three major body

sections, is given to an

extinct group of marine

arthropods characteristic

of the period in question?

5 What dismissive name is

sometimes given to a long

period of apparent stasis in

evolution, starting around

1.8 billion years ago, before

the emergence of animals?

Answers below

Quick

Crossword #42

Answers

ACROSS 1 Altered States,

8 Yeti, 9 Betelgeuse, 10 Foetus,

11 HackBook, 12 Westworld,

14 Sine, 15 Tank, 16 Eddington,

20 Pumpkins, 21 Oil rig,

23 Branestawm, 24 Thaw,

25 Bernstein test

DOWN 1 Anemone, 2 Twist,

3 RuBisCO, 4 Dutch elm disease,

5 Telica, 6 Trembling, 7 Systole,

13 Tin opener, 15 True rib,

17 Iron man, 18 Oxidant,

19 Miosis, 22 Litre

Quick quiz #24

Answers

brian explosionThe Cam 1

The Burgess Shale 2

Stephen Jay Gould 3

Trilobites 4

The boring billion 5







  



   



  

 

ACROSS

7 One who fishes can be

obtuse medic (6)

8 Overly sentimental morally

suspect beetle (6)

9 Wager indigenous wildlife,

inferior in pack life (4)

10 Geological period concealed

Monty Python’s alternative

Messiah (8)

11 Unpredictable task, a

sudden movement (7)

13 Fool Armageddon trial (5)

15 Cordon off a wetland love

affair (5)

17 Natural material belongs

to me, the Queen’s

Scottish residence (7)

20 Stick to mature geological

splitting (8)

21 Portable surface intended

for beam (4)

23 Meet poem to conceal

messages (6)

24 Rubbish used for fishing

gemstone (6)

Answers and the next quick crossword next week.

In this Tectonic crossword, every answer is formed by the

subduction of one word under another. For example, CLIFF might

subduct under ROCK to form CROCK. The traditional definition is

always at one end of the clue, and clues to the two subducting

words appear in the same order as their answers.

DOWN

1 Bet worker or queen, for

example, Indian currency (4)

2 European mountain,

destination of the Odyssey’s

star South American

mammal (6)

3 Rock playwright Bertolt’s

intelligence service (7)

4 Did the breaststroke, not

down marshland (5)

5 Support fathers’ facial hair (6)

6 The almighty New Orleans

dish mountain (8)

12 Mathematician Bernhard:

“throw out white wine!” (8)

14 Pretend to have been fouled,

push, go separate ways (7)

16 Stable part of the Earth’s

crust splits a lot (6)

18 Complete doorway anger (6)

19 Gemstone surface confronts

1982 alien (5)

22 Top primate fornication (4) Get in touch

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