Practice Pakistan's most useful MCQs for competitive exams

Pick up the correct statement?

• (A)  closed cycle gas turbine is an I.C engine
• (B)  gas turbine uses same working fluid over and over again
• (C)  air-fuel ratio in a gas turbine is 100 : 1
• (D)  ideal efficiency of closed cycle gas turbine plant is more than carnot cycle efficiency
• (E)  thrust in turbo-jet is produced by nozzle exit gases

Answer

Submitted By :Ali Uppal

Pick up the false statement ?

• (A)  gas turbine is a self-starting unit
• (B)  gas turbine does not require huge quantity of water like steam plant
• (C)  exhaust losses in gas turbine are high due to large mass flow rate
• (D)  overall efficiency of gas turbine plant is lower than that of a reciprocating engine
• (E)  gas turbine can be easily started and stopped and thus is best suited for peaking demands

Answer

Submitted By :Ali Uppal

Pick up the wrong statement?

• (A)  In a heterogeneous or solid-fuel reactor, the fuel is mixed in a regular pattern within moderator.
• (B)  Slow or thermal neutrons have energy of the order or 0.025 eV
• (C)  Fast neutrons have energies above 1000 eV
• (D)  Fast reactor uses moderator
• (E)  Most serious drawback in using water as coolant in nuclear plants is its high vapour pressure

Answer

Submitted By :Ali Uppal

The angle which an inclined plane makes with the horizontal when a body placed on it is about to move down is known as angle of_______________?

• (A)  friction
• (B)  limiting friction
• (C)  repose
• (D)  kinematic friction
• (E)  static friction

Answer

Submitted By :Ali Uppal

In ideal machines__________________?

• (A)  mechanical advantage is greater than velocity ratio
• (B)  mechanical advantage is equal to velocity ratio
• (C)  mechanical advantage is less than velocity ratio
• (D)  mechanical advantage is unity
• (E)  none of the above

Answer

Submitted By :Ali Uppal

In actual machines_______________?

• (A)  mechanical advantage is greater than velocity ratio
• (B)  mechanical advantage is equal to velocity ratio
• (C)  mechanical advantage is less than velocity ratio
• (D)  mechanical advantage is unity
• (E)  none of the above

Answer

Submitted By :Ali Uppal

A cable with a uniformly distributed load per horizontal meter run will take the following shape________________?

• (A)  straight line
• (B)  parabola
• (C)  hyperbola
• (D)  elliptical
• (E)  part of a circle

Answer

Submitted By :Ali Uppal

The algebraic sum of moments of the forces forming couple about any point in their plane is_________________?

• (A)  equal to the moment of the couple
• (B)  constant
• (C)  both of above are correct
• (D)  both of above are wrong
• (E)  none of the above

Answer

Submitted By :Ali Uppal

A semi-circular disc rests on a horizontal surface with its top flat surface horizontal and circular portion touching down. The coefficient of friction between semi-cricular disc and horizontal surface is \i. This disc is to be pulled by a horizontal force applied at one edge and it always remains horizontal. When the disc is about to start moving, its top horizontal force will____________________?

• (A)  remain horizontal
• (B)  slant up towards direction of pull
• (C)  slant down towards direction of pull
• (D)  unpredictable
• (E)  none of the above

Answer

Submitted By :Ali Uppal

Tangent of angle of friction is equal to__________________?

• (A)  kinetic friction
• (B)  limiting friction
• (C)  angle of repose
• (D)  coefficient of friction
• (E)  friction force

Answer

Submitted By :Ali Uppal