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Magnitudes and Scale

How do we represent really big numbers?

Task 1

View the prezi below


Task 2

State the approximate value of the following quantities in SI units to the nearest order of magnitude.  The first two have been answered for you as examples.

1) Length of a day

SI unit for time = second.  1 hour = 60 mins, 1 min = 60 seconds so 24 hours = 86400 seconds = 8.64 x 104 seconds.

2) Mass of a bus

If we say a bus is approximately 2 tons, 2 tons is 2000kg (kg is the SI unit for mass)

= 2 x 103 kg

REMEMBER - your answer must be in SI units and standard form!

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.

4) The size of a microbe (the clue is in the name!).

5) The energy in a snack of your choice.

6) The width of your hand.

7) The height of a door.

8) The width of your thumb nail.

9) The number of seconds you have been calculating these answers!

10) Your age (yes it is constantly changing but this is an estimate...)


Share your answers on your blog and post a link in the comments section below.

Task Discussion