Surveying Multiple Choice Questions on “Ideal Transition Curve”.
1. A curve which is having a varying radius is called _____________
a) Simple curve
b) Compound curve
c) Transition curve
d) Reverse curve
Answer: c
Clarification: A transition curve is having a varying radius which is introduced in between the branches of different curves. It is used in areas where a straight line and a curve have to be connected.
2. In order to prevent the case of overturning, which of the following is provided?
a) Super elevation
b) Reverse curve
c) Simple curve
d) Compound curve
Answer: a
Clarification: Super elevation is provided in such a way that there is a rise at a side of the curve which helps in avoiding overturning, which is given as B/gR which helps in determining the amount of elevation needed to be provided.
3. The provision of equilibrium cant can be seen in case of__________
a) Curves
b) Mountains
c) Highways
d) Railways
Answer: d
Clarification: The provision of equilibrium cant can be seen in case of railways, which is capable of providing the same amount of load on either side of the track, which makes the passenger not to lean in any direction.
4. Side friction factor is used in which of the following cases?
a) Reverse curve
b) Transition curve
c) Simple curve
d) Compound curve
Answer: b
Clarification: Side friction factor is the force transferred by friction to the pavement, which can be used in case of highways while providing super elevation to avoid overturning of vehicles.
5. With increase in super elevation there must be subsequent increase in centrifugal force for balancing it.
a) True
b) False
Answer: a
Clarification: While considering super elevation, the weight of the vehicle and centrifugal force must be taken into consideration. So if there is an increase in super elevation, centrifugal force must be increased so that it balances the motion with less frictional force.
6. Length of transition curve can be given as __________
a) L = r tan(δ/2)
b) L = ne
c) L = n – e
d) L = n + e
Answer: b
Clarification: Length of transition curve is given as L = ne in which, e describes about the amount of super elevation provided which should be at a required rate and n varies in between 300 to 1200.
7. Which of the following methods doesn’t describe the method of finding length of transition curve?
a) Arbitrary gradient
b) Time rate
c) Bisection of arcs
d) Rate of Change of radial acceleration
Answer: c
Clarification: The length of transition curve depends upon amount of super elevation provided which must be at a required rate. It can be determined by an arbitrary gradient, time rate and change of radial acceleration.
8. Among the methods available for determining the length of the curve, which is commonly used?
a) Bisection of arcs
b) Time rate
c) Arbitrary method
d) Rate of change of radial acceleration
Answer: d
Clarification: In the rate of change of radial acceleration, time rate methods length is directly proportional to which makes both of them useful. But, in accuracy perspective, rate of change of radial acceleration method is used most commonly.
9. Clothoid is also known as___________
a) Glover’s spiral
b) Froude’s equation
c) Cartesian curve
d) Cubic spiral
Answer: a
Clarification: A clothoid is an ideal transition curve in which, length is inversely proportional to the radius of the curve. It is also known as Glover’s spiral.
10. Froude’s transition is also known as___________
a) Clothoid
b) Cubic parabola
c) Cubic spiral
d) Glover’s spiral
Answer: b
Clarification: Cubic parabola is also known as Froude’s transition curve. It uses Cartesian co-ordinates which are required for setting the curve. It is the most commonly used transition curve, which can use rectangular co-ordinates too.
11. Determine the super elevation, if the width of the road can be given as 2.96m, radius of curve as 62.96m, vehicle speed = 56m/s.
a) 51.303m
b) 51.03m
c) 15.03m
d) 15.3m
Answer: c
Clarification: Super elevation or cant can be derived by,
e = Bv2/g*R. on substitution, we get
e = 2.96*562 / 9.81*62.96
e = 15.03m.
12. If the super elevation for a road is given as 24m, find the length of transition curve.
a) 15.6 km
b) 15.6 m
c) 15.6 cm
d) 15.6 mm
Answer: a
Clarification: The length of transition curve can be determined by,
L = n*e, the value of n varies in between 300-1200. Assume the value of n = 650. On substitution, we get
L = 650*24
L = 15600 m. = 15.6 km.
13. Using intrinsic equation, find the value of the length of curve between two points of a 45m transition curve having radius 24.76m with an inclination of 8˚43ꞌ.
a) 319.37m
b) 913.37m
c) 139.73m
d) 139.37m
Answer: d
Clarification: From the intrinsic equation,
( l = sqrt{2RLθ}.) On substitution, we get
(l = sqrt{2*24.76*45*8˚43ꞌ})
l = 139.37m.
14. If the radius of curvature of a curve being 45.42m with an inclination of 7˚52ꞌ. The value of s and L corresponds to 2 and 56m respectively, find the total tangent length of a transition curve.
a) 03.02m
b) 30.02m
c) 2.3m
d) 3.2m
Answer: b
Clarification: The total length of a transition curve can be determined by,
(R+s)*tan (θ/2) + L*(1 – (frac{s}{R})) / 2. On substitution, we get
= (45.42+2)*tan (7˚52ꞌ/2) + 56*(1 – (frac{2}{45.42})) / 2
= 30.02m.
15. In a cubic parabola, if the value of x co-ordinate is 7, radius of the curve is given as 42.69m and the length of the curve as 24m. Find the y co-ordinate.
a) 2.76
b) 1.05
c) 0.05
d) 5
Answer: c
Clarification: The value of y co-ordinate can be determined by using the formula,
y = x3 / 6*R*L. on substitution, we get
y = 73 / 6*42.69*24
y = 0.05.