Unit IV the basic machines

lever – важіль, рукоятка

rigid – жорсткий

bar – стрижень

fulcrum – точка опори, центр обертання

effort – зусилля

axle – вісь, вал

crank – кривошип

a bent shaft – зігнутий вал

vice versa – навпаки

groove – робити проріз, паз, нарізку

rim – скоба, обід

pulley – шків

housing – корпус, кожух

tackle – складний блок, устаткування

wedge – клин

taper – конус, звужуватися

Inclined plane – похила площина

screw – гвинт

helical – спіральний

helix – спіраль, спіральна лінія

cork screw – штопор, гвинтоподібний, спіральний

jack – домкрат, важіль

stick – палиця

pry – піднімати

seesaw – гойдалка

topple – валити, перекидати

wheelbarrow – тачка

foot-treadle – ніжна педаль

lengthen – подовжувати, розтягувати

exert – докладати (зусиль)

arm – плече, рукоятка

log – поліно, колода

chariot – колісниця

clay - глина

stream – потік

divert – відводити

hoisting – підняття

leverage –система важелів, підйомна сила

suspend – підвішувати

upward –спрямований вгору

split – розбивати, розколювати

apart – окремо

quarry –здобич, добувати каміння

axe - сокира

hail – цвях

compute – обчислювати, підраховувати

breadth – ширина

ramp – похила площина

Special Terms:

Lever: A basic machine con­sisting of a rigid piece or bar that turns on a point.

Fulcrum: The point on which a lever turns.

Effort End: The point where force is applied to a lever.

Load End: The point where there is resisting force on a lever.

Wheel and Axle: A basic machine consisting of a wheel that rotates on a shaft called the axle.

Crank: A bent shaft or arm for transmitting motion or changing from rotary to reciprocating motion and vice versa.

Pulley: A basic machine con­sisting of a wheel with a grooved rim through which a rope, wire, or chain is passed.

Block: A pulley contained in housing; the combina­tion of a fixed and a movable block together with a rope is known as a block and tackle.

Wedge: A basic machine con­sisting of a piece of material tapering to a thin edge.

Inclined Plane: A basic ma­chine; at its simplest a surface at an angle to the horizon.

Screw: A basic machine sometimes described as a helical inclined plane or a cylinder with a helical groove around the outer surface.

Helix: The corkscrew-shaped figure that results from wrapping the line of an inclined plane around a cylinder; the plural is helices.

Jack: A device used to raise heavy weights for short distances.

Vocabulary Practice:

1. What is a lever?

2. What part of the lever is the fulcrum?

3. What is the difference between the effort end and the load end of a lever?

4. What does a wheel and axle consist of?

5. What does a crank do?

6. Describe a pulley.

7. What is a block? What does a block and tackle consist of?

8. What is a wedge?

9. What is an inclined plane?

10. Describe a screw.

11. What is the shape of the helix?

12. What is a jack?