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The correct option is (d) Positive DISPLACEMENT

Easiest explanation: Eaton5^th generation supercharger is a root’s TYPE positive displacement pump with no INTERNAL COMPRESSION. Each of the tri-lobe ROTORS are twisted to 60 degrees to reduce noise.

Right option is (d) 0

To explain: When the boosted PRESSURE is equal to the COMPRESSION pressure of the supercharger, the backflow is ZERO. SINCE the backflow is zero, further the air is forcefully INJECTED and higher power is obtained.

The correct option is (a) True

Easy EXPLANATION: Smaller turbochargers have less TURBO lag than larger ones, so OFTEN two SMALL turbochargers are used instead of one large one. Hence, the statement is true.

Correct CHOICE is (d) Turbo-normalized engine

Best EXPLANATION: Systems that USE a turbocharger to maintain an engine’s sea-level power out are called turbo-normalized systems. Generally, it maintain a manifold pressure of 100KPA.

Correct option is (a) Intake manifold

Best EXPLANATION: The TURBOCHARGER’s compressor DRAWS in ambient air and compresses it before it enters into the intake manifold at an INCREASED pressure to the CYLINDER.

Correct choice is (d) Pumping loss

To explain I would say: A TURBOCHARGER does not place a direct mechanical load on the ENGINE, although turbochargers place EXHAUST back PRESSURE on engines, increasing pumping LOSSES.

Right answer is (a) Twin-charging

The best I can explain: Compared with a MECHANICALLY driven SUPERCHARGER, turbochargers tend to be more EFFICIENT, but LESS RESPONSIVE. Twin-charger refers to an engine with both a supercharger and a turbocharger.

The CORRECT option is (b) Turbine

The best I can explain: SUPERCHARGER is mechanically driven by the engine, often through a belt connected to the CRANKSHAFT, WHEREAS a TURBOCHARGER is powered by a turbine.

Correct CHOICE is (d) Throttle lag

For explanation: Throttle lag is the DISADVANTAGE of TURBOCHARGER. This occurs because turbocharger rely on the buildup of EXHAUST gas pressure to drive the turbine.

Right option is (d) Exhaust GAS

To elaborate: Both the supercharger and the TURBOCHARGER perform the same FUNCTION, the supercharger is driven directly by the engine, WHEREAS a turbocharger is driven by exhaust gas.

The correct ANSWER is (c) Aircraft engine

The EXPLANATION: The centrifugal-type SUPERCHARGER has been used mainly on aircraft engines, WHEREAS the roots-type supercharger is used in automobile engines.

Right choice is (a) Screw TYPE

The explanation is: Screw type supercharger compresses the air between TWO intermeshing SCREWS, taking it at one END and compressing the air as it travels ALONG the screw axis.

The CORRECT answer is (a) HIGH strength

To explain: The properties REQUIRED for a vane material are quiet running, low friction, low coefficient of thermal expansion, and resistance to continuous exposure to oil and PETROL.

The correct OPTION is (a) Root’s type

Best explanation: Root’s SUPERCHARGER consists of two rotors of EPICYCLOID shape. An epicycloid is the locus of a point on the CIRCUMFERENCE of a circle which rolls on ANOTHER circle.

The correct CHOICE is (d) Alloy steel

To EXPLAIN I WOULD say: The impeller runs at a very high speed, which should be ABLE to take the ACCOMPANYING stresses at such high speeds. Generally, impellers are made of duralumin, or alloy steels.

Correct CHOICE is (b) CENTRIFUGAL type

The explanation: In centrifugal-type SUPERCHARGER, the air/fuel mixture enters the impeller at the center and after passing through the impeller and the diffuser VANE, it enters the volute casing.

The correct answer is (d) Scavenging

Easy EXPLANATION: In two-STROKE engines, scavenging is required to PURGE exhaust gasses, as well as charge the cylinders for the NEXT POWER stroke. In small engines, this requirement is commonly met by using the crankcase as a blower.

Right answer is (d) Detonation

The EXPLANATION: ONE of the disadvantages of SUPERCHARGING is that compressing the AIR INCREASES its temperature. Extreme temperature will cause detonation of the fuel-air mixture.

Correct ANSWER is (d) Centrifugal and multi-stage axial FLOW

The explanation: DYNAMIC COMPRESSORS rely on accelerating the air to high speed. MAJOR types of dynamic compressors are centrifugal and multi-stage axial flow.

Right OPTION is (b) False

To elaborate: INTERNAL compression devices usually use a fixed internal compression ratio. When the boosted PRESSURE is equal to the compression pressure of the supercharger, the backflow is ZERO.

Right CHOICE is (a) Capacity PER revolution

Explanation: Positive displacement SUPERCHARGERS are usually rated by their capacity per revolution. In this case of the ROOTS blower, the GMC RATING pattern is typical.

The correct CHOICE is (a) Dynamic COMPRESSOR

Explanation: Positive DISPLACEMENT supercharger deliver an ALMOST constant level pressure increase at all ENGINE RPM; above the threshold, speed pressure increases exponentially in a compressor.

Right answer is (d) Positive displacement

To explain: Positive displacement supercharger deliver an almost constant LEVEL PRESSURE INCREASE at all engine RPM and DYNAMIC compressor does not deliver pressure at low speeds; above the threshold, SPEED pressure increases exponentially.

Correct option is (a) Positive displacement and dynamic COMPRESSORS

To explain: There are two main types of superchargers defined ACCORDING to the METHOD of GAS TRANSFER, they are positive displacement and dynamic compressors.

Right choice is (d) Crankshaft

To elaborate: POWER for the supercharger can be provided MECHANICALLY USING a belt, GEAR, shaft, or chain connected to the engine’s crankshaft. Whereas, turbocharger is driven by EXHAUST gas.

Right answer is (a) True

To explain I would say: Combined RESONANCE and ABSORBER type muffler is a combination of both resonance and absorber type. This CONTAINS FIBERGLASS as a noise absorbing material.

Correct answer is (d) Absorber type

The BEST explanation: In absorber type muffler, the sound is reduced by CONVERSION into heat by sound-absorbing material. Such MUFFLERS are commonly known as GLASS packed mufflers.

The correct option is (d) Compressor

To elaborate: A SUPERCHARGER is an AIR compressor that increases the PRESSURE of air supplied to an INTERNAL combustion engine. This GIVES each intake cycle of the engine more oxygen.

Right OPTION is (d) Absorber type

Easiest explanation: In absorber type muffler, the sound-absorbing MATERIAL, USUALLY fiberglass, is placed in this case around the perforated tube through which the EXHAUST gases PASS.

Right option is (c) HELMHOLTZ TYPE

To ELABORATE: Resonance type muffler is ALSO called a Helmholtz type, after the person who originated the idea. It consists of several Helmholtz resonators in SERIES.

Correct answer is (c) Light TYPE

To EXPLAIN I would say: Baffle type, WAVE cancellation type, Resonance type, ABSORBER type, and Combined resonance and absorber type are all the types of MUFFLERS. Whereas light type is not a muffler.

Right answer is (B) Wave cancellation TYPE

For EXPLANATION I would say: In wave cancellation type, the length of these paths is so adjusted that after they come out of the muffler, the crest of one wave coincides with the TROUGH of the second wave, thus reducing noise.

Correct option is (a) Restriction of exhaust gas

To elaborate: The MAJOR DRAWBACK of the baffle muffler is their low efficiency. Because of the restriction provided to the flow by the baffles, the backpressure is INCREASED thus causing a LOSS in ENGINE power.

Right option is (d) MUFFLER

For EXPLANATION I would say: A tailpipe CARRIES the EXHAUST gases from the muffler to the rear or side of the vehicle near the wheel. Muffler reduces noise by canceling the waves.

The correct answer is (a) Silencer

The explanation: To reduce the noise, the ENGINE EXHAUST is CONNECTED via an exhaust PIPE to the silencer, which is also called muffler. Muffler reduces noise by canceling the waves.

Correct option is (c) 3000 to 10000Hz

The EXPLANATION: haust GASES have a very high temperature and PRESSURE, when this STRIKES the walls of the exhaust system, they produce a high-frequency notes from 3000 to 10000Hz.

Right option is (d) HIGH pressure

Explanation: When the EXHAUST valve opens, the high-pressure exhaust gas is RELEASED, which causes a pressure wave in the AIR causing an explosion.