Questions set 69

Wheel and Tire

1.      Which types of wheels cannot be used with a tubeless tire?
a) Disc wheel
b) Light alloy wheel
c) Wire wheel
d) Composite wheel
Answer: c
Explanation: Wire wheels cannot be used with a tubeless tire. Wire wheels are expensive due to their construction. The rim of a wired wheel has holes, due to which it is not possible to fit tubeless tires on wire wheels.

2.      Which type of wheels is preferred in sports cars?
a) Disc wheel
b) Wire wheel
c) Magnesium alloy wheel
d) Aluminum alloy wheel
Answer: c
Explanation: Magnesium alloy wheels are preferred in sports cars. Magnesium alloy wheels have high impact and fatigue strength so that they can stand vibration and shock loading better.

3.      In case of a wire wheel, the vehicle weight is supported by the wire in _________
a) Tension
b) Bending
c) Shear
d) Compression
Answer: a
Explanation: The vehicle weight is supported by the wire in tension in case of a wire wheel. The side forces on cornering are taken up by the spoke forming triangular arrangement.

4.      What does the ‘ply rating’ refer to?
a) Aspect ratio
b) Rated strength
c) Recommended inflation pressure
d) The actual number of plies
Answer: b
Explanation: The ‘ply rating’ refers to rated strength. It is referred to the number of layers of cotton from which the ply is made. The ply rating is high that means the size of the tire is tough.

5.      Where will an underinflated tire wear the thread most?
a) Near center
b) Near the edge
c) In the cross direction
d) In the lateral direction
Answer: b
Explanation: An underinflated tire will wear the thread near the edge most. It is sometimes visible in the shape of sidewall cracking.

6.      Where will an overinflated tire wear the thread most?
a) Near center
b) Near the edge
c) In the cross direction
d) In the lateral direction
Answer: a
Explanation: An overinflated tire will wear the thread near the center. This type of tire break is caused when an object is hit with a force.

7.      What do the permissible of mixing cross-ply and radial-ply automobile tires allow?
a) Cross-ply tires on left wheels
b) Cross-ply tires on right wheels
c) Cross-ply tires on front wheels
d) Cross-ply tires on rear wheels
Answer: c
Explanation: The permissible of mixing cross-ply and radial-ply automobile tires allow cross-ply tires on front wheels. In cross-ply type tires, the ply cords are woven at an angle to the tire axis.

8.      What is the purpose of tire rotation on automobiles?
a) Avoid ply separation
b) Equalize wear
c) Get better ride
d) Reduce bump
Answer: b
Explanation: Equalize wear is the purpose of tire rotation on automobiles. The advantage of tires wearing uniformly is wear reduces a tire’s tread depth equally if all the tires wear at the same rate.

9.      A car is fitted with 6 * 14 wheels and 185/65 R 14 tires on them. What is the rolling radius of the original tire?
a) 398.05 mm
b) 298.05 mm
c) 288.05 mm
d) 278.05 mm
Answer: b
Explanation: Radius of the wheel = ½ * 14 = 7 in = 177.8 mm. Section height of tire = 0.65 * 185 = 120.25 mm. Rolling radius of the original tires = 177.8 + 120.25 = 298.05 mm.

10.  What does the code 145 SR -13 tire designation represent?
a) 145” width, 13” diameter, cross-ply
b) 145 mm width, 13” diameter, radial-ply
c) 145” width, 13 cm diameter, radial-ply
d) 145 mm width, 13 cm diameter, cross-ply
Answer: b
Explanation: The tire designation is of the form width (mm), speed rating, type of ply, and diameter (in) in the same order. So 145 SR – 13 signifies that width = W = 145 mm, speed rating = S which is up to 170 Kmph, the ply is of radial type, and diameter = 13” or 13 in = 330 mm.