SI units conversion

Question 1

mega

Answer 1

M

1 000 000 or 10^6

Question 2

kilo

Answer 2

k

1 000 or 10^3

Question 3

deci

Answer 3

d

1/10 or 0.1 or 10^-1

Question 4

centi

Answer 4

c

1/100 or 0.01 or 10^-2

Question 5

milli

Answer 5

m

1/1000 or 0.001 or 10^-3

Question 6

micro

Answer 6

μ

1/1000000 (6 zeros) or 0.000001 (5 zeros after first whole no digit) or 10^-6

Question 7

What do you leave your answers in for addition, subtraction and average?

Answer 7

to the least number of decimal places

• Eg. 1.2 + 0.456 = 1.7 (1 d.p.)
- 3. Average of 3 measurements: 6.5s, 7.2s. 6.6s
= 6.8 s (Apply the least d.p. rule since it is a calculation of average)

Question 8

What do you leave your answers in for multiplication, division and the rest of operations ?

Answer 8

to the least amount of significant figures

• Eg. 5.25 x 10 = 53 (2 s.f.)

Question 9

what numbers are significant?

Answer 9

every number except zeros used before the first non-zero digit are significant (e.g. 0.3 is in 1 s.f., but 3.0 is in 2 s.f.)