Assistant Motor Vehicle Inspector part 6

031. What type of fusion welding process is used for welding sheet metals of all

engineering metals (except Cu, Ag) in

automobile and air craft industries, pipe and tubing production?

Resistance welding.

032. In DC arc welding, if leads are arranged in work as Positive pole of the welding arc and electrode as Negative pole of the welding arc, the arrangement is known as

Straight polarity.

033. What is the type of joining process called, where the parts to be welded are kept in contact and rotated relative to each other and axial pressure is applied when

the desired temperature

is obtained?

Friction welding.

034. In a shaper

Work is stationary, and tool reciprocates.

035. Orthographic projection is also known as

Multi view projection.

036. The distance a screw thread advances

axially in one turn is the

Lead.

037. This is the theoretically exact size from which limits of size are determined

Basic size

038. The coefficient of friction depends on

nature of surface.

039. Limiting force of friction is the

the friction force acting when the body is just about to move

040. Which of the following has no unit?

Strain.

041. When shear force at a point is zero, then bending moment is maximum

at that point.

042. The point of contra flexure occurs in

overhanging beams

043. If the intake air temperature of I.C. engine increases, its efficiency will

decrease.

044. In a typical medium speed 4-stroke cycle diesel

engine the inlet valve

opens at 20° before top dead center and closes at 35° after the bottom dead center.

045. The pressure and temperature at the end of compression stroke in a petrol engine are of

the order of

6 – 12 kg/cm2 and 250 – 350°C.

046. The maximum temperature in the I.C.

engine cylinder is of the order of

2000 – 2500°C.

047. The thermal efficiency of a diesel cycle having fixed compression ratio, with increase in cut-off ratio will

decrease.

048. Combustion in compression ignition

engines are

heterogeneous.

049. The inlet valve of a four-stroke cycle I.C. engine remains open for nearly

235°.

051. The output of a diesel engine can be increased without increasing the engine revolution or size in following way

supercharging.

052. Because of detonation in an I.C. engine, following parameter attains very high value

rate of rise of pressure.

053. Most high-speed compression engines operate on

Dual combustion cycle

056. Which of the following medium is compressed in a Diesel engine cylinder?

air alone.

057. The air-fuel ratio of the petrol engine is controlled by

Carburetor.

058. Diesel fuel compared to petrol is

more difficult to ignite.

059. A 75 CC engine has following parameter as 75 CC

swept volume.

060. Engine pistons are usually made of aluminium alloy because it

is lighter.