measurement and uncertainty

The unit m³ is used to express

• length

• mass

• volume

• density

SI base units for length and mass are

• centimeter

• meter and gram

• centimeter and kilogram

• meter and kilogram

How many significant figures does the following number have: 0.002040

• 6
• 4
• 3
• 2

How many significant figures does the following number have: 0.998005

• 9
• 10
• 6
• 5

Express 23400 in proper scientific notation. 

• 2.34 x 10⁴
• 2.3 x 10³
• 2.30 x 10⁵
• 2.34 x 10³

How would you write 564,000,000 in scientific notation?

• 5.64 x 10^-7
• 5.64 x 10⁶
• 5.64 x 10⁸
• 56.4 x 10⁷

Express the following in scientific notation:
0.000457

• 457 x 10⁶

• 457 x 10^-6

• 4.57 x10⁴

• 4.57 x 10^-4

True or False?

Repeating a reading never removes the systematic error.

• True

• False

The diagram shows a micrometer scale

• 5.64 mm

• 7.14 mm

• 7.16 mm

• 7.64 mm

A student intends to measure accurately the diameter of a wire (known to be approximately 1 mm) and the internal diameter of a pipe (known to be approximately 2 cm).

What are the most appropriate instruments for the student to use to make these measurements [(i) wire, (ii) pipe]?

• (i) calipers, (ii) calipers

• (i) calipers, (ii) micrometer

• (i) micrometer, (ii) calipers

• (i) micrometer, (ii) micrometer