3. Answer the following questions:

   1. What is strength theory?

   2. What does strength theory include?

   3. What is the subject of strength theory?

   4. In what fields of science is strength theory widely used?

   5. What do you know about the earliest researchers of the strength of materials?

   6. What famous scientists of the 18^th century do you know?

   7. What do you know about Mohr-Coulomb Strength Theory?

3. Match the words with their definitions:

strength, theory, mechanics, material, scientist, subject, stress.

1. Set of rules or principles for the study of a subject.

2. Anything from which something is or can be made.

3. The thing that is dealt with or represented in theory.

4. Force of weight caused by pressure.

5. Something providing force or power.

6. The science of the action of forces on objects.

7. A person who works in a science.

3. Put these words in to the right order to make sentences:

1. deals, yield, failure, materials, stress, a, with, state, Strength, under, and, complex, theory, the, of.

2. Strength, widely, physics, mechanics, science, earth, science, engineering, used, is, theory, in, material, and.

3. Strength, a, unusual, wonderful, very, subject, is, and, theory.

4. Galilei, among, scientists, that, Galileo, da Vinci, most, of, and, Leonardo, outstanding, the, were, period.

5. Da Vinci, strength, wire, significantly, length, that, would, on, of, an, iron, its, depend, the, believed.

6. shear, Coulomb, the, the, first, theory, may, maximum, researcher, strength, be, in, stress.

7. multiaxial, Strength, general, includes, criteria, failure, as, fatigue, criteria, yield, is, term, and, theory, as, criteria, a, well.

5. Make up word combinations from the following words, translate them into Ukrainian:

   1. shear a) body

   2. cohesive b) stress

   3. elastic c) theory

   4. critical d) resistance

   5. strength e) utilization

   6. fatigue f) plane

   7. effective g) criteria

7. Decide whether the statements below are true or false:

   1. Strength theory is widely used in physics, mechanics and material science.

   2. Coulomb was the researcher in the minimum shear stress strength theory.

   3. Timoshenko -1878-1972 was an outstanding scientist, distinguished engineer, and a great and inspiring professor.

   4. No other scientist of the eighteenth century contributed as much as Coulomb did to the science of physics of solid bodies.

   5. Leonardo da Vinci and Galileo Galilei may be the earliest researchers of the strength of materials and structures.

   6. The paper began with a discussion of experiments which Coulomb made for the purpose of establishing the stress of some kind of sandstone.

   7. Coulomb's Memoir Essay was read by him to the Academy of France on March 10 and April 2, 1773, and published in London in 1776.