Question

The minimum distance required for a vehicle to overtake a vehicle without interfering with a vehicle coming in the opposite direction at a design speed of about 80 kmph is .........

• A. 340 m
• B. 470 m
• C. 570 m
• D. 640 m

Hint:

Overtaking sight distance increases significantly with speed—always consult the latest IRC tables while designing highways.

Answer 1

The Correct Option is B

Step 1: Understand the scenario.
When a vehicle overtakes another on a two-lane road, it temporarily moves into the lane of oncoming traffic. To avoid collision, a minimum overtaking sight distance is required.
Step 2: Refer to IRC standards.
According to the Indian Roads Congress (IRC:66), the minimum overtaking sight distance depends on the design speed.
Step 3: Use standard values.
For a design speed of 80 kmph, the recommended overtaking sight distance is 470 m. This value is derived from IRC tables based on typical acceleration, reaction time, and safe clearance distance.
Step 4: Eliminate other options.
- 340 m is suitable for lower speeds like 60 kmph
- 570 m and 640 m are for higher speeds like 100 kmph or more
Step 5: Conclusion.
Hence, the correct minimum overtaking distance at 80 kmph is 470 m.