1.1 Use of SI Units and their Prefixes

Question 1

What are the 7 SI base Units?

Answer 1

Luminous intensity, mass, temperature, electric current, length, amount of a substance and time.

Question 2

What is the SI base Unit for light intensity?

Answer 2

Candela (cd)

Question 3

What is the SI base Unit for current?

Answer 3

Ampere (A)

Question 4

What is the SI base Unit for mass?

Answer 4

Kilogram (kg)

Question 5

What is the SI base Unit for length?

Answer 5

Metre (m)

Question 6

What is the SI base Unit for time?

Answer 6

Seconds (s)

Question 7

What is the SI base Unit for amount of a substance?

Answer 7

Moles (mole)

Question 8

What is the SI base Unit for temperature?

Answer 8

Kelvin (K)

Question 9

What is the SI base Unit for power?

Answer 9

kgm^2⋅s^−3

Question 10

What does the prefix P mean?

Answer 10

Peta

x10^15

Question 11

What does the prefix T mean?

Answer 11

Tera

x10^12

Question 12

What does the prefix G mean?

Answer 12

Giga

x10^9

Question 13

What does the prefix M mean?

Answer 13

Mega

x10^6

Question 14

What does the prefix k mean?

Answer 14

Kilo

x10^3

Question 15

What does the prefix c mean?

Answer 15

Centi

x10^-2

Question 16

What does the prefix m mean?

Answer 16

Milli

x10^-3

Question 17

What does the prefix μ mean?

Answer 17

Micro

x10^-6

Question 18

What does the prefix n mean?

Answer 18

Nano

x10^-9

Question 19

What does the prefix p mean?

Answer 19

Pico

x10^-12

Question 20

What does the prefix f mean?

Answer 20

Femto

x10^-15

Question 21

What is the SI Unit of power?

Answer 21

Watt (W)

Question 22

How to convert from eV to J?

Answer 22

x (1.6 x 10^-19)

Why?
1eV = 1.6 x 10^-19

Question 23

How to convert form kWh to J?

Answer 23

x (3.6 x 10^6)
or
x 3,600,000

Why?
1kwh = 1,000W x 3,600s = 3,600,000 J