Answers

Answers
 
3) If an average person has a mass of 60kg, and the world population is currently around 7 billion people, estimate the mass of the human race.
 
1 person= 60kg
60 × 7000000000 = 420000000000
= 4.2×10¹¹ kg
 
4) The size of a microbe.
 
micrometer= one millionth of a meter
=1÷1000000
=1×10¯⁶m
 
5) The energy in a snack of your choice.
 
1 apple= 253kj
253kj= 253000j
= 2.53×10⁵j
 
6) The width of your hand.
 
hand width= 10cm
10cm= 0.1m
=0.1m
 
7) The height of a door
 
=2m
 
8) The width of your thumb nail.
 
thumb nail width= 1.5cm
1.5cm= 0.015m
= 0.015m
 
9) The number of seconds you have been calculating these answers.

30 mins= 30×60s
=1800s
=1.8×10³s

10) Your age

16years= 16×365=5840
5840×24=140160
140160×60=8409600
8409600×60=50476000
50476000s
=5.05×10⁷ s (3.s.f)