Cetane number of $\alpha$-methyl naphthalene is

Octane number of a fuel can be increased by adding

The main object of morse test is to find out

Piston of diesel engines are usually cooled by

Consider the following statements:

1. In a carburetor the throttle value is used to control the fuel supply.

2. The fuel level in the float chambers is to be about 4 to 5 mm below the orifice level of main jet.

3. An idle jet provides extra fuel during sudden acceleration.

4. A choke value restricts the air supply to make the gas richer with fuel.

Which of these statements are correct?

Assertion (A): In SI engine, as the engine speed increases, spark is required to be advanced.

Reason (R): As the engine speed increases flame velocity increases.

In a SI engine, combustion stage-I takes 1 ms and combustion stage-II takes 1.5 ms when the engine runs at 1000 rpm. If stage-I time duration independent of engine speed. What will be the additional spark advance necessary when the engine speed is doubled?

The bore and stroke of the cylinder of a 6 – cylinder engine working on an Otto-cycle are 17 cm and 30 cm respectively, and total clearance volume is 9225 cm³, then what is the compression ratio?

Pre-Ignition in SI engine results in:

1. Increase in the work of compression

2. Increase in the network of the process cycles.

3. Decrease in fuel efficiency

4. Decrease in fuel loss from the engine

In SI engine, for higher thermal efficiency

In a two-stroke petrol engine, fuel loss is maximum after:

Knocking in a spark ignition engine can be reduced by

1. Retarding the spark

2. Supercharging

3. Increasing the engine speed

4. using a fuel of long straight chain structure

Select the correct answer using the code given below.

Consider the following statements regarding C.I. engine :

1. C.I. engines are more bulky than S.I. engines.

2. C.I. engines are more efficient than S.I. engines.

3. Lighter flywheels are required in C.I. engines.

Which of the above statements are correct?

Statement (I) : A good CI engine fuel is bad SI engine fuel and a good SI engine fuel is a bad CI engine fuel.

Statement (II) : A CI engine fuel require high self-ignition temperature and a long delay period whereas a SI engine fuel requires low self-ignition temperature and short delay period.

Air injection in IC engines refers to injection of

The delay period in CI engine depends upon which of the following?

A 4-stroke diesel engine, when running at 2000 rpm has an injection duration of 1.5 ms. What is the corresponding duration of the crank angle in degrees?

Which one of the following fuels can be obtained by fermentation of vegetable matter?

Methane burns with stoichiometric quantity of air. The air fuel ratio by weight is

Consider the following statements:

1. Octane rating of gasoline is based on iso-octane and n-heptane fuels which are paraffins.

2. Tetraethyl lead is added to gasoline to increases octane number

3. Ethylene di-bromide is added as scavenging agent to remove lead deposits on spark plugs.

4. Surface ignition need not necessarily cause knocking.

Which of these statements are correct?

A 4-cylinder diesel  Engine running at 1200 rpm developed 18.6 kW. The average torque when one cylinder was cut out was 105 N m. If the calorific value of the fuel was 42000 kJ/kg and the engine used 0.34 kg of diesel/kW hr, the indicated thermal efficiency was nearly

In a Morse test of a 2-cylinder, 2-stroke SI engine, the brake power is 9 kW and the BHP of individual cylinders with spark cutoff are 4.25 kW and 3.75 kW respectively. The mechanical efficiency of the engine is

A single cylinder, 4-stroke cycle engine is fitted with a rope brake. The diameter of the brake wheel is 600 mm and the rope diameter is 26 mm, the dead weight on the brake is 200 N and the spring balance reads 30 N. If the engine runs at 450 rpm, what will be the brake power of the engine?

A spark ignition engine has a compression ratio of 8 and the volume before compression is 0.9 m³/kg. Net heat interaction per cycle is 1575 kJ/kg. What is the mean effective pressure?

Which one of the following engines will have heavier flywheel than the remaining one?

Keeping other parameters constant, the brake power of diesel engine can be increased by

The three way catalytic converter cannot control which one of the following?

Which one of the following set of materials is most commonly used in catalytic converters for CI engines?

Consider the following emission of an IC Engine:

1. CO

2. HC

3. NO_x

4. Particulates

Which of the following causes photo chemical smog?

Match List-I (Gas Cycles) with List-II (Thermodynamic coordinates) and select the correct answer using the codes given below the lists:

Isothermal compression of air in a stirling engine is an example of

Consider the following the statements:

1. Both Otto and Diesel cycles are special cases of dual combusting cycle

2. Combusting process in IC engines is neither fully constant volume nor fully constant pressure

3. Combusting process in ideal cycle is replaced by heat addition from internal source in closed cycle.

4. Exhaust process is replaced by heat rejection in ideal cycle.

Which of the above statements are correct?

Which fuel cell is suitable for spacecraft applications?

Which of the following features(s) is/are used in the combustion chamber design to reduce SI engine knock?

In a standard dual air cycle, for a fixed amount of heat supplied and a fixed value of compression ratio, the mean effective pressure

A two stroke engine has a speed of 750 rpm. A four stroke engine an identical cylinder size runs at 1500rpm. The theoretical output of the two engine will

Pyrheliometer is use to measure

Lead compounds were added in gasoline to

Olefins are generally represented by

Consider the following statements for a combustion process:

1. The total mass of each chemical element in the reactants is preserved in the products.

2. The presence of carbon monoxide in the products of combustion implies incomplete combustion.

Which of the above statements is/are correct?