Explore topic-wise MCQs in Physics.

This section includes 21 Mcqs, each offering curated multiple-choice questions to sharpen your Physics knowledge and support exam preparation. Choose a topic below to get started.

1.

Theoretically, a four stroke cycle engine should develop __________ power as that of a two stroke cycle engine.

A. double
B. half
C. same
D. four times
Answer» C. same
2.

The energy released during the fission of one atom of Uranium – 235 in million electron volts is about

A. 200
B. 300
C. 100
D. 400
Answer» B. 300
3.

In a four stroke cycle diesel engine, the exhaust valve

A. opens at bottom dead centre and closes at top dead centre
B. opens at 60° after top dead centre and closes at 10° before top dead centre
C. opens at 30° before bottom dead cnetre and closes at 10° after top dead centre
D. may open and close anywhere
Answer» D. may open and close anywhere
4.

Morse test is used to determine the I.P. of a

A. four stroke engine
B. single cylinder diesel engine
C. single cylinder petrol engine
D. multi-cylinder engine
Answer» E.
5.

The working pressure and temperature inside the cylinder of an internal combustion engine is __________ as compared to a steam engine.

A. very low
B. very high
C. high
D. low
Answer» C. high
6.

A moderator

A. absorbs neutrons
B. accelerates neutrons
C. does not absorb neutrons
D. none of these
Answer» D. none of these
7.

The advancing of spark timing in spark ignition engines will __________ knocking tendency.

A. none of these
B. reduce
C. increase
D. not effect
Answer» D. not effect
8.

The correct mixture strength (by weight) for petrol is about

A. 14.6:1
B. 22.6:1
C. 20.4:1
D. 18.5:1
Answer» B. 22.6:1
9.

The inlet valve of a four stroke cycle internal combustion engine remains open for

A. 130°
B. 180°
C. 270°
D. 230°
Answer» E.
10.

Supercharging __________ the power developed by the engine.

A. all of these
B. increases
C. decreases
D. has no effect on
Answer» C. decreases
11.

Which of the following statement is correct regarding petrol engines?

A. all of the above
B. The fuel supplied to the engine cylinder is mixed with necessary amount of air and the mixture in ignited with the help of a spark plug.
C. The fuel is first evaporated after passing through a carburettor and is mixed with air before ignition.
D. A fine fuel spray mixed with air is ignited by the heat of compression which is at a high pressure.
Answer» C. The fuel is first evaporated after passing through a carburettor and is mixed with air before ignition.
12.

The colour of exhaust from diesel engine is generally.

A. bluish
B. A. white
C. black
D. violent
Answer» D. violent
13.

The knocking in spark ignition engines can be reduced by

A. none of these
B. increasing the engine speed
C. both (a) and (b)
D. retarding the spark
Answer» D. retarding the spark
14.

The maximum propulsive efficiency of a turbo-jet engine is at a speed of

A. 3000 km/h
B. 1000 km/h
C. 2000 km/h
D. 2400 km/h
Answer» E.
15.

In order to mix air and petrol in the required proportion and to supply it to the engine during suction stroke, then __________ is employed.

A. carburettor
B. fuel pump
C. injector
D. none of these
Answer» B. fuel pump
16.

Which one of the following event would reduce volumetric efficiency of a vertical compression ignition engine ?

A. inlet valve opening before top dead centre
B. exhaust valve closing after top dead centre
C. inlet valve closing before bottom dead centre
D. inlet valve closing after bottom dead centre
Answer» D. inlet valve closing after bottom dead centre
17.

A moderator, apart from its high neutron slowing power, and low non-productive neutron, should be

A. corrossion resistant
B. stable under nuclear radiation
C. good thermal conductor
D. all of these
Answer» E.
18.

The delay period in compression ignition engines depends upon

A. nature of the fuel mixture strength
B. relative velocity between the fuel injection and air turbulence pressure of residual gases
C. temperature and pressure in the cylinder at the time of injection
D. all of the above
Answer» E.
19.

The frictional power (F.P.) is given by

A. F.P. = I.P. - B.P.
B. F.P. = B.P. - I.P.
C. F.P. = B.P./I.P.
D. F.P. = I.P./B.P.
Answer» B. F.P. = B.P. - I.P.
20.

The nuclear radiators produced in a reactor which must be sheilded are

A. electrons
B. none of these
C. α, β and γ rays
D. neutron and gamma rays
Answer» E.
21.

he material most commonly used for sheilding is

A. lead
B. carbon
C. concrete
D. all of these
Answer» D. all of these