37.

38.

39.

40.

41.

42.

099/23

Identify the wrong statement.

1. The knocking tendency in Cl engines increase with increasing the temperature
of inlet air.

2. To avoid knock in SI engine, the combustion chamber must have large bore.

3. Detonation in SI engine occurs due to pre-ignition of change before spark is
struck.

4. Advancing the spark timing in spark ignition engines leads to reduce the knocking
tendency.

A) 1 and 2 are wrong 8) 1, 2 and 4 are wrong

C) 3 and 4 are wrong D) All are wrong

A Carnot refrigerator having the capacity of 15 tonnes. The higher temperature of
the refrigerant in the system is 27°C and the lower temperature is —23°C. What is
the work input value in Md/hr ?

A) 42 B) 36

C) 30 D) 24
Helmholtz free energy (F) relation is

A) F=U+TS B) F=U-TS

‎F=H+TS D) F=H-TS‏ ره

‎In hydrodynamic boundary layer, the energy, momentum and displacement thickness
are observed to be 1/18, 1/15 and 1/3 respectively. The shape factor value will be

‎A) 1.2 B) 3

‎Cc) 5 D) 6

‎When trying to turn a key into a lock is applied.
A) Lever B) Coplanar force
C) Couple D) Moment

‎A stone of mass m at the end of a string length / is whirled in a vertical circle at a
constant speed. The tension in the string will be maximum when the stone is

‎A) Atthe top of the circle

‎B) Half-way down from the top

‎C) Quarter was down from the top
)

‎ட) At the bottom of the circle