D42 MASTER THE DAY

Which instrument is used to check right angles in chain surveying?

• Line ranger
• Cross staff
• Telescope
• Arrow

Answer explanation

Cross staff is a simple instrument used for setting out right angles in the field.

What is the permissible error for a 20 m chain as per IS 1492?

• ±2 mm
• ±5 mm
• ±10 mm
• ±8 mm

Answer explanation

According to IS 1492, the permissible error in a 20 m chain is ±5 mm.

What is the purpose of folding chains after use?

• For lubrication
• For easy storage and transport
• To reduce weight
• To correct errors

Answer explanation

Chains are folded in a specific way to allow easy handling, storage, and transport.

How many arrows are provided with a 30 m chain?

• 10
• 20
• 9
• 15

Answer explanation

Each chain is supplied with 10 arrows to mark every full chain length measured.

The zero end of a chain is generally marked by:

• Brass ring
• Arrow head
• Tally
• Red ribbon

Answer explanation

A brass ring is attached to the zero end of the chain for identification.

Which method is used to avoid cumulative errors in chain surveying?

• Using new chain every time
• Standardizing the chain
• Replacing links
• Using measuring tape

Answer explanation

Standardizing ensures the chain is of correct length before and after the survey.

What is the main function of a ranging rod?

• Measure distance
• Determine elevation
• Align survey lines
• Take offsets

Answer explanation

Ranging rods are used for aligning the survey line between two stations.

Which is the standard length of a Gunter's chain?

• 20 m
• 30 m
• 66 ft
• 100 ft

Answer explanation

Gunter’s chain is 66 ft long and used primarily in English system of measurement.

What is the effect of temperature on chain measurement?

• No effect
• Shortens chain
• Lengthens chain
• Only affects steel tape

Answer explanation

Higher temperature causes thermal expansion, increasing chain length and introducing error.

Which line is run to locate interior details in chain surveying?

• Check line
• Tie line
• Base line
• Offset line

Answer explanation

Tie lines are used to locate interior details and also help in checking measurements.