Physics - Measurement Units

Physics A-Level

​MEASUREMENT AND UNITS

by Dwi Febriana

​Physical Quantity

​Physical quantities have a numerical value and a unit. In physics, it is essential to give the units of physical quantities.

​

​You might write the mass of the laptop as:

​

mass of the laptop = 2 kg

SI Systems

The scientific system of units is called the Système Internationale d’Unités (or SI system). The seven base units of this system are listed in below:

Multiple Choice

SI stands for ___.

• Sports Illustrated

• Scientific Notation

• International System (of measurements)

• Instructional System (of measurements)

Multiple Choice

What SI unit is used to measure time?

• seconds
• amperes
• Kelvin
• mole

Multiple Choice

What does the prefix milli- mean?

• 1/100
• 100
• 1,000
• 1/1,000

Multiple Choice

What prefix is represented by the following symbol:  h

• hecto
• kilo
• deci
• deka

Multiple Choice

The SI unit for measuring volume is the __?__.

• meter (m)
• liter (L)
• cubic meter (m³)
• gram (g)

Multiple Choice

The SI unit for measuring mass is the
 __?__.

• meter (m)
• liter (L)
• cubic meter (m³)
• kilogram (kg)

Multiple Choice

Newtons could be used to measure __________ and __________.

• mass, speed

• momentum, work

• force, weight

• direction, power

Multiple Choice

What is the unit for momentum, ρ?

• Moments

• kg ms^-1

• kg ms^-2

• inertia

Multiple Choice

What is the unit for power, P?

• Watt

• Volt

• Ampere

• Joule

Multiple Choice

Wiggins is trying to find the density of an ice cube. First, he measures the cube and sees that its mass is 80 kilograms. Then, he measures the length of the cube and determines that each side is 2 m long. Determine how dense the ice cube that Wiggins is measuring.

• 40 kg/m³

• 10 kg/m³

• 8 kg/m³

• 640 kg/m³

• There is not enough information to determine the density of the ice cube.

Multiple Choice

How many cm are in 1 km?

• 100000 cm
• 1 cm
• 10000 cm
• 100 cm

Multiple Choice

ms^-1 is the unit for ...

• acceleration

• velocity

• momentum

• force

Multiple Choice

What is the unit for kinetic energy, E_k?

• Watt

• Joule

• Volt

• Newton

Multiple Choice

What is the unit for acceleration?

• ms^-2

• ms^-1

• Nm

• Nm^-1

Multiple Choice

Seconds are the S.I. units for ...

• distance

• velocity

• speed

• time

Prefixes

​In physics, you will have to cope with very small and very large numbers. Numbers are written using powers of 10 to make them less awkward. This is known as scientific notation.

Prefixes are used as an abbreviation for some of the powers of 10.

Prefixes

​In physics, you will have to cope with very small and very large numbers. Numbers are written using powers of 10 to make them less awkward. This is known as scientific notation.

Prefixes are used as an abbreviation for some of the powers of 10.

Prefixes

​In physics, you will have to cope with very small and very large numbers. Numbers are written using powers of 10 to make them less awkward. This is known as scientific notation.

Prefixes are used as an abbreviation for some of the powers of 10.

Multiple Choice

Which one of these options is NOT a fundamental quantity?

• Time

• Electric current

• Energy

• Luminous Intensity

Multiple Choice

What is the SI unit of electric current?

• Ampere (A)

• Volt (V)

• Ohm

• Mole

Multiple Choice

What is the DIMENSION of length?

• [M]

• [L]

• [T]

• [l]

Multiple Choice

What is the DIMENSION of time?

• [M]

• [L]

• [T]

• [l]

Multiple Choice

Which one of these options is NOT a derived quantity?

• Area

• Volume

• Density

• Temperature

Multiple Choice

What is the SI unit of speed?

• m/s

• cm/s

• km/hour

• kg/m

Multiple Choice

1 nm (nano-meter) = .... m

• 1 x 10^-12

• 1 x 10⁹

• 1 x 10^-9

• 1 x 10¹²

Multiple Choice

In 2008 Olympic Game, Usain Bolt sets world record at 10 s in Men’s 110 m Final. What is his average speed ?

• 1100 ms

• 11 m/s

• 10 m/s

• 0.09 m/s

Multiple Choice

What is the DIMENSION of acceleration?

• L³

• [L/T]

• [L/T²]

• LT

Multiple Choice

a, b, and c have units of meters, s = a, what is dimension of s, [s] ?

• [M]

• [L]

• [M/L]

• [ML]

Multiple Choice

a, b, and c have units of meters, s = a + b, what is the dimension of s, [s]?

• [M]

• [L]

• [M/L]

• [ML]