D42 CHECK YOUR LEVEL

What is the principle used in GPS to determine position?

• Triangulation
• Trilateration
• Interpolation
• Rectification

Answer explanation

GPS uses the principle of Trilateration to determine positions by intersecting distances from multiple satellites.

Which component of a cantilever retaining wall acts like a vertical cantilever under lateral earth pressure?

• Heel
• Toe
• Stem
• Weep hole

Answer explanation

The stem is the upright part of a cantilever retaining wall and acts like a vertical cantilever resisting lateral earth pressure.

In a one-way slab, what is the typical effective depth provided for a span up to 1 m with 500 kg/m² load?

• 2 cm
• 4 cm
• 6 cm
• 8 cm

Answer explanation

Effective depth of 4 cm is recommended per meter span for loading up to 500 kg/m² in one-way slabs.

Which component of the railway track transfers loads from rails to ballast?

• Rail
• Sleeper
• Ballast
• Subgrade

Answer explanation

Sleepers transfer the load from rails to the ballast.

Which type of canal alignment is most economical and requires the least cross drainage works?

• Contour Canal
• Ridge Canal
• Side Slope Canal
• Navigation Canal

Answer explanation

Ridge canals run along the watershed line and require fewer cross drainage works, making them economical.

Which of the following is a defect in timber due to fungi?

• Knot
• Blue stain
• Twist
• Wane

Answer explanation

Blue stain is caused by fungal action in sap wood, leading to a bluish discoloration.

Which type of vernier has its scale division less than the main scale division?

• Backward vernier
• Extended vernier
• Direct vernier
• Double vernier

Answer explanation

Direct vernier or forward vernier has its vernier scale division less than the main scale division.

Which type of retaining wall is most suitable for heights greater than 8 m?

• Gravity wall
• Counterfort wall
• Buttressed wall
• Cantilever wall

Answer explanation

Counterfort walls are economical and structurally efficient for walls taller than 8 m.

Which element improves corrosion resistance in steel?

• Manganese
• Chromium
• Carbon
• Silicon

Answer explanation

Chromium improves the corrosion resistance of steel.

Which is a factor affecting the selection of railway gauge?

• Wheel size
• Length of sleepers
• Speed of trains
• Type of fasteners

Answer explanation

Speed of trains is a major factor in determining the gauge width.