In practice, the compression ratio of compression-ignition (CI) engine ranges from ______________________?

Related Mcqs:

1. Work required for compression of a gas contained in a cylinder is 7000 kJ. During compression, heat interaction of 3000 kJ causes the surroundings to be heated. Internal energy change of the gas during the compression is __________________ kJ ?

   A. +4000
   B. -4000
   C. 10000
   D. -10000

2. Multistage compression of air as compared to single stage compression offers the advantage of______________?

   A. Power saving per unit weight of air delivered
   B. Moisture elimination in the inter-stage cooler
   C. Increased volumetric efficiency
   D. All A , B. & C.

3. Otto cycle used in spark ignition petrol engines is also known as the constant ________________ cycle?

   A. Volume
   B. Pressure
   C. Heat
   D. None of these

4. With increase in compression ratio, the volumetric efficiency of air compressor____________________?

   A. Increases
   B. Decreases
   C. Remain same
   D. May increase or decrease (depends on the suction pressure)

5. Air-petrol ratio in an automotive petrol engine is around ________________?

   A. 14 : 1
   B. 22 : 1
   C. 25 : 1
   D. 4 : 1

6. Current employed in resistance welding ranges from ____________________ kVA/cm2?

   A. 1.2 to 2.5
   B. 4.5 to 6.2
   C. 7.5 to 8.5
   D. 10.5 to 15.5

7. The ratio of mass of a neutron to that of an electron is about 1839. What is the ratio of the mass of a proton to that of an electron ?

   A. 159
   B. 1837
   C. 2537
   D. 10000

8. Two wires of the same radius & material having length in the ratio of 1 : 2 are stretched by the same force. The strain produced in the two wires will be in the ratio of__________________?

   A. 1 : 1
   B. 1 : 2
   C. 2 : 1
   D. 1 : 4

9. The ratio of thermal & electrical conductivity is same for all the metals at the same temperature; and at around room temperature, this ratio is proportional to(where, T = absolute temperature, °K) ?

   A. T
   B. 1/T
   C. T2
   D. 1/T2

10. The behaviour of a metal specimen, which when plastically strained in tension reduces its yield stress in compression and vice versa; is termed as the_______________?

    A. Work hardening
    B. Bauschinger effect
    C. Creeping effect
    D. Stress recovery effect