Sec 3 Physical Quantities, units and measurement

Physical quantities are quantities that consist of a numerical ​ (a)   and an ​ (b)   .

• magnitude
• unit
• direction
• symbol
• prefix

What is a base quantity?

• A base quantity is a physical quantity that is defined in terms of other quantities.
• A base quantity is a unit of measurement.
• A base quantity is a mathematical equation.
• A base quantity is a physical quantity that is not defined in terms of other quantities, but is used to define other quantities.

Organize these options into the right categories

Groups:

(a) base quantities

,

(b) derived quantites

• time

• energy

• amount of substance

• density

• temperature

• mass

• force

• pressure

• area

• volume

• current

• length

Match the following prefix to its multiples / factors.

• 10⁶

• micro

• 10^-6

• centi

• 10^-9

• mega

• 10^-2

• kilo

• 10³

• nano

What is 3 μg equivalent to?

• 0.3 grams
• 0.000003 grams
• 0.003 grams
• 3 milligrams

How much is 8.9 MJ?

• 890,000 joules
• 89,000 joules
• 8,900,000 joules
• 8,900 joules

• 8.96 x 10⁵ m

• 8.96 x 10² m

• 8.96 x 10³ m

• 8.96 x 10⁶ m

The symbol for mega is ​ (a)   and the symbol of tera is ​ (b)   .

• M
• T
• m
• t

What is the order of magnitude of a atom?

• 10^-10 m

• 10 nm

• 10¹⁰ m

• 10 km

Match the following smallest interval to the respective measuring instruments.

• 0.01 s

• digital stopwatch

• 0.001 cm

• metre rule

• 0.001 mm

• digital micrometer screw gauge

• 0.001 m

• digital calipers