V. Find an appropriate word for each blank space:

1. The speed at which no frictional … is required to maintain the vehicle in … is called the «hands off» speed.

2. Maximum … are based on drivers’ feelings of comfort with the higher values causing discomfort.

3. There are the alternatives for … of less than the maximum curvature.

4. Friction … for curvature increase rapidly and drivers are, in effect, presented with two different types of curves, and hence a more complicated judgment … is necessary.

5. This tendency will have to be counteracted by … of steering out of the curve.

VI. Decide whether the statements are true or not. Correct the wrong ones:

1. The value of the coefficient of friction for a treaded tire on an icy surface is about 0,2.

2. The speed at which no frictional force is required to maintain the vehicle in the curve is called the «hands off» speed.

3. Maximum side friction factors are based on drivers’ feelings of comfort with the higher values causing comfort.

4. There are the alternatives for superelevating curves of less than the maximum curvature.

5. Method 1 overcomes this latter difficulty by applying superelevation to accommodate the average speed.

6. Method 3 is theoretically logical but does not allow for the common tendency to drive faster on shallow curves.

7. This tendency will have to be counteracted by the irrational manoeuvre of steering out of the curve.

VII. Answer the following questions:

1. What is the value of the coefficient of friction for a treaded tire on an icy surface?

2. How is the speed at which no frictional force is required to maintain the vehicle in the curve called?

3. What are maximum side friction factors based on?

4. What are the alternatives for superelevating curves?

5. When is the method of sufficient superelevation applied?

6. When is the superelevation curvature relationship parabolic and tangential to the sides of triangle?

VIII. Divide the text into some logical parts.

IX. Write out all the key words from the text.

X. Make up a plan of the text; prepare a short report on the text.

3.5 Transition Curves

PRE-TEXT EXERCISES

Ι. Mind the pronunciation of the following words:

1.	instantaneous		[ˌɪn(t)stən'teɪnɪəs]	миттєвий
2.	straight	[streɪt]		прямий
3.	radius	['reɪdɪəs]		радіус
4.	infinity	[ɪn'fɪnətɪ]		нескінченність
5.	disjoint	[dɪs'ʤɔɪnt]		відділення
6.	spiral	['spaɪər(ə)l]		спіраль
7.	parabola	[pə'ræb(ə)lə]		парабола
8.	arc	[ɑːk]		дуга
9.	magnitude	['mægnɪt(j)uːd]		величина
10.	negotiate	[nɪ'gəuʃɪeɪt]		обмірковувати

ΙI. Word-combinations to remember:

a straight path – прямолінійна траєкторія;

circular curve –­ кругова траєкторія;

transition curve – перехідна крива;

constant radius – незмінний радіус;

to present a visually pleasing line – представляти візуально приємну лінію;

tangent point – точка дотику;

leading dimensions – основні розміри;

cubic parabola – кубічна парабола;

to be dependent on the vehicle's speed – залежати від швидкості транспортного засобу;

unbalanced sideways force – незбалансована бічна сила;

the magnitude of the force – величина сили;

total length of curve – загальна довжина кривої.