Civil Engineering All Engineering Career

The correct answer is "angle of intersection."

The angle between the back tangent and forward tangent of a curve is known as the angle of intersection. This angle is crucial in road design and alignment to ensure smooth transitions between different segments of a curve.

The correct answer is "positive error."

The error in measured length due to sag of a chain or tape is known as a positive error. This happens because the sag causes the measured length to be longer than the actual length.

The corrected answer is "check line."

A line joining the apex of a triangle to some fixed point on the opposite side is called a check line. It is used to verify and ensure the accuracy of the framework or layout in surveying.

The correct answer is "30 m."

For flat curves, the typical length of the peg interval is 30 meters. This spacing is used to mark points along the curve to aid in surveying and alignment.

The correct answer is "all of the above."

Chain surveying is most suitable when:

• The area to be surveyed is small.
• The ground is fairly level and open with simple details.
• Plans are required on a large scale.

These conditions allow for accurate and efficient use of chain surveying techniques.

The correct answer is "open cross-staff."

An open cross-staff is used for setting out an offset at a right angle to a survey line. It's a simple instrument with sighting slots at right angles, allowing for accurate perpendicular measurements.

The correct answer is "reflection."

The optical square measures angles by using the principle of reflection. It reflects the line of sight off a mirrored surface to accurately determine angles.

The correct answer is "true meridian."

The true meridian is the line that intersects the Earth's surface through a given point and the North and South Poles. It represents the direction of the Earth's geographic north-south axis.

The correct answer is "odometer."

An odometer is an instrument attached to the wheel of a vehicle to measure the distance traveled. It records the total distance covered by the vehicle.

The correct answer is "azimuth."

The horizontal angle between the true meridian and a survey line is called the azimuth. It measures the direction of the survey line with respect to the true north.