Chapter 2 - Quantities And Units

Question 1

What is a physical quantity ?

Answer 1

a physical quantity is a property of an object or of a phenomenon that can be measured

Question 2

Whats the base unit for length ?

Answer 2

Metre - m

Question 3

Whats the base unit for mass ?

Answer 3

Kilogram - kg

Question 4

Whats the base unit for time ?

Answer 4

Second - s

Question 5

Whats the base unit for electric current ?

Answer 5

Ampere = A

Question 6

Whats the base unit for temperature ?

Answer 6

Kelvin - K

Question 7

Whats the base unit for amount of substance ?

Answer 7

Mole - mol

Question 8

Whats the factor for peta - P ?

Answer 8

10*15

Question 9

Whats the factor for tera - T ?

Answer 9

10*12

Question 10

Whats the factor for giga - G ?

Answer 10

10*9

Question 11

Whats the factor for mega - M ?

Answer 11

10*6

Question 12

Whats the factor of kilo - k ?

Answer 12

10*3

Question 13

Whats the factor for deci - d ?

Answer 13

10*-1

Question 14

Whats the factor of centi - c ?

Answer 14

10*-2

Question 15

What’s the factor of milli - m ?

Answer 15

10*-3

Question 16

Whats the factor of micro - weird u ?

Answer 16

10*-6

Question 17

Whats the factor of nano - n ?

Answer 17

10*-9

Question 18

Whats the factor of pico - p ?

Answer 18

10*-12

Question 19

What’s the factor of femto - f ?

Answer 19

10*-15

Question 20

Whats a scalar quantity ?

Answer 20

A scalar quantity has magnitude (size) but no direction

Question 21

How do you add/subtract scalar quantities ?

Answer 21

You can only add scalar quantities if they are the same unit for e.g. you can’t add 1min + 30secs and do 1+30 - you would have to convert rather 1min into secs then add

Question 22

Can you divide and multiply scalar quantities?

Answer 22

Yes you can and it can have different units - the units don’t have to be the same for you to subtract and multiply 2 scalar quantities

Question 23

Whats a vector quantity ?

Answer 23

A vector quantity has magnitude and direction

Question 24

Whats distance and displacement measured in ?

Answer 24

Metres - m
However displacement is a vector quantity and distance is a scalar quantity

Question 25

What do you do when 2 vectors are parallel ?

Answer 25

If they are parallel (act in the same line and direction), you just add them together to find the resultant vector

Question 26

What do you do when there are 2 vectors that are anti parallel (they act in the same line but in opposite directions ) ?

Answer 26

Subtract the bigger one from the smaller one and the resultant vector will be acting in the direction of the bigger force