11.RRB ALP CBT2 RAC Question bank

RAC

The most common insulating material used in cold storage is ……….

• PUF
• Thermocole
• Cork
• Glass wool

PUF stands for ……….

• Poly user foam
• Poly urea foam
• Polyurethane foam
• Polyuria urethane foam

A cork insulation with a waterproof binder is used for ………. Surfaces.

• Soft
• Hot
• Cold
• Hard

Bimetallic strips composed of two different metals each having a different rate of thermal expansion are used in –

• Thermostats
• Pressure Cookers
• Heat Engines
• Pressure Gauges

The most commonly used insulating material in water cooler is-

• Fiber Glass
• PUF
• Cord
• Glass Wool

Fouling of heat transfer surfaces-

• Decreases insulating effect
• Has no insulating effect
• Increases insulating effect
• None of these