Words and word combinations to be remembered

matter – вещество, материал	compare – сравнивать	use – использовать
electric current – электрический ток	define – определять, устанавливать	modify – видоизменять, трансформировать
voltage – напряжение	obtain – получать	amount of substance – количество вещества
length – длина	multiply – умножать	luminous intensity – сила света
decimal system – десятичная система	divide – делить	mole – моль
a set of – ряд, серия, набор	carry out – проводить	candela – кандела

Ex. 1. Translate from Russian into English:

Теплота, единица измерения, величина, напряжение, международное соглашение, усмотрение, свойства вещества, точность измерений, развивающаяся система, основная единица, физическая величина, длина, простота, полностью, признавать, изменять, улучшаться, принять, заменить, состоять из, определять, сравнить, умножать, делить.

Ex. 2. Translate the following sentences. Make up all possible questions:

1. We are familiar with the idea that measurement requires a system of units.

2. For scientific and engineering purposes there are several quantities of fundamental significance.

Ex. 3. Match the words in 2 columns, what do these expressions mean? Make up your own sentences with these word combinations:

To measure	a unit
To improve	into 2 classes
To adopt	with the standard
To divide	volume
To modify	the International System of Units
To define	the precision of measurements
To compare	with electricity, magnetism, heat, light
To establish	unit definition
To agree	to use
To deal	metrication

Ex. 4. Fill in the blanks:

1. A trained physicist must be able to measure accurately … as well as other quantities such as electric current and voltage.

2. Every physical quantity has its own unit of … .

3. Other units used are obtained from the metre by … .

4. In the 20^th century scientists agreed to use a particular system in science, called … .

5. The International System of Units was established in … .

6. Prefixes and units are created and unit definitions are modified as the technology of measurement … , and as the precision of measurements … .

7. The International System of Units consists of … .

8. The units are divided into two classes … .

Ex. 5. Say in English:

a) In the British system: 1 mile (mi) = 1,760 yd; 1 yd = 3 ft; 1 ft = 12 in

b) In the metric system: 1 km = 1000 m; 1 m = 100 cm; 1 cm = 10 mm

c) Do you know that ...

1 in = 25.3995 mm? 1 ft = 30.479 cm? 1 yd = 0.9144 m? 1 mile = 1.6093 km?

Ex. 6. Choose the right word:

1. Unit is a (quality / quantity) adopted as a standard of measurement. 2. Foot is a unit of (area / length) in the English system of measurement. 3. Inch is (more / less) than foot is. 4. There are 12 (yards / inches) in 1 foot. 5. Velocity is length (multiplied / divided) by time. 6. The second is a unit for measuring time in (MKS system / all the systems). 7. (Dimension / division) is a mathematical operation. 8. The square metre is an MKS unit of (area / volume). 9. 11.500 cubic feet is the measure of (area / volume / mass).

Ex. 7. Answer the following questions:

1. What does physics deal with? 2. What do we need to make any measurement? 3. What unit does a physicist use to measure the weight of a body? 4. What is the unit of length? 5. What was the Metric System designed for? 6. What does the International System of Units consist of? 7. How many classes are the units of measurement divided into?

Ex. 8. Say a few words about:

• accuracy

• ways to define a unit

• M.K.S. system

• the International System of Units