D27 FACE THE CHALLENGE

Which of the following is a derived unit?

• Metre
• Second
• Newton
• Kilogram

Answer explanation

Newton is the SI unit of force, derived from base units.

Which of the following is a scalar quantity?

• Velocity
• Displacement
• Force
• Work

Answer explanation

Work has magnitude but no direction, hence it is scalar.

The ratio of load lifted to effort applied in a machine is called:

• Velocity ratio
• Efficiency
• Mechanical advantage
• Output ratio

Answer explanation

Mechanical advantage = Load / Effort.

Stress is defined as:

• Force × Area
• Force / Area
• Area / Force
• Strain / Force

Answer explanation

Stress is internal resistance per unit area developed in a body.

The unit of energy in SI system is:

• Watt
• Joule
• Newton
• Erg

Answer explanation

Joule is the SI unit of energy.

The foundation of a bridge that is built in water is called:

• Pier
• Abutment
• Well foundation
• Deck

Answer explanation

Well foundations are used in deep waters to support bridge piers.

Which is the most commonly used rail section in India?

• Double headed
• Bull headed
• Flat footed
• Grooved rail

Answer explanation

Flat footed rails are widely used in Indian Railways for strength and stability.

The function of ballast in railway track is to:

• Support sleepers
• Transfer load to rails
• Provide signaling
• Provide water drainage only

Answer explanation

Ballast holds sleepers in place and distributes load.

Which type of road is constructed without bitumen or cement?

• Water bound macadam
• Bituminous road
• Concrete road
• National Highway

Answer explanation

WBM roads use crushed stone aggregates and screening material.

Which of the following is a type of steel bridge?

• Timber truss
• Cable stayed
• RCC girder
• Masonry arch

Answer explanation

Cable stayed bridges use steel cables for support.