Question 1 |

A streamline and an equipotential line in a flow field

Are parallel to each other | |

Are perpendicular to each other | |

Intersect at an acute angle | |

Are identical |

Question 1 Explanation:

Stream line and equipotential line in a flow field are perpendicular to each other

Question 2 |

If a mass of moist air in an airtight vessel is heated to a higher temperature, then

Specific humidity of the air increases | |

Specific humidity of the air decreases | |

Relative humidity of the air increases | |

Relative humidity of the air decreases |

Question 2 Explanation:

The moist air in an airtight vessel is heated to a higher temperature. This process is treated as sensible heating. In sensible heating process, the relative humidity of the air decreases with increase in dry bulb temperature at constnat specific humidity

This process is shown on psychrometic chart in Fig.

This process is shown on psychrometic chart in Fig.

Question 3 |

In a condenser of a power plant, the steam condenses at a temperature of 60^{\circ}C. The cooling water enters at 30^{\circ}C and leaves at 45^{\circ}C. The logarithmic mean temperature difference (LMTD) of the condenser is

16.2^{\circ}C | |

21.6^{\circ}C | |

30^{\circ}C | |

37.5^{\circ}C |

Question 3 Explanation:

\begin{aligned} \therefore \quad \mathrm{LMTD} &=\frac{\Delta T_{1}-\Delta T_{2}}{\ln \left(\frac{\Delta T_{1}}{\Delta T_{2}}\right)} \\ &=\frac{30-15}{\ln (2)}=21.64^{\circ} \mathrm{C} \end{aligned}

Question 4 |

A simply supported beam PQ is loaded by a moment of 1kN-m at the mid-span of the beam as shown in the figure. The reaction forces R_{P}
and R_{Q}
at supports P and Q respectively are

1kN downward, 1kN upward | |

0.5kN upward, 0.5kN downward | |

0.5kN downward, 0.5kNupward | |

1kN upward, 1kN upward |

Question 4 Explanation:

Let us assume the direction of R_{P} and R_{Q} as ,

upward. Now,

\therefore \quad R_{P}+R_{Q}=0

\therefore Taking moment about point Q we get:

\begin{aligned} R_{P} \times 1+1 &=0 \\ R_{P} &=-1 \mathrm{kN}\\ \therefore R_{Q}&=+1 \mathrm{kN} \end{aligned}

since our assume direction of R_{p} is wrong therefore

R_{P}=1 \mathrm{kN} which act in the down was direction

and R_{Q}=1 \mathrm{kN} acting in upward direction.

Question 5 |

A double - parallelogram mechanism is shown in the figure. Note that PQ is a single link. The mobility of the mechanism is

-1 | |

0 | |

1 | |

2 |

Question 5 Explanation:

This is a special case because the link between & parallel to P and Q is redundant as its presence does not effect the mechanism. Hence the DOF is 1.

Question 6 |

The maximum possible draft in cold rolling of sheet increases with the

Increase in coefficient of friction | |

Decrease in coefficient of friction | |

Decrease in roll radius | |

Increase in roll velocity |

Question 6 Explanation:

The main objective in rolling is to decrease the thickness of the metal.

The relation for the rolling is given by

F=\mu P_r

where,

F= tangential frictional force

\mu = Coefficient of friction

P_r= Normal force between the roll and work piece

Now, from the increase in \mu, the draft in cold rolling of sheet increases.

The relation for the rolling is given by

F=\mu P_r

where,

F= tangential frictional force

\mu = Coefficient of friction

P_r= Normal force between the roll and work piece

Now, from the increase in \mu, the draft in cold rolling of sheet increases.

Question 7 |

The operation in which oil is permeated into the pores of a powder metallurgy product is known as

Mixing | |

Sintering | |

Impregnation | |

Infitration |

Question 7 Explanation:

Operation in which oil is permeated into the pores of powder metallurgy product is known as impregnation.

Question 8 |

A hole is of dimension \phi 9^{_{+0}^{+0.015}} mm.
The corresponding shaft is of dimension \phi 9^{_{+0.001}^{+0.010}} mm. The resulting assembly has

Loose running fit | |

Close running fit | |

Transition fit | |

Interference fit |

Question 8 Explanation:

It is case of transition fit

Since

Since

Question 9 |

Heat and work are

Intensive properties | |

Extensive properties | |

Point functions | |

Path functions |

Question 9 Explanation:

Heat and work are path function. These are not point function.

Question 10 |

A column has a rectangular cross-section of 10mm x 20mm and a length of 1m. The slenderness ratio of the column is close to

200 | |

346 | |

477 | |

1000 |

Question 10 Explanation:

Assuming both ends of column to be hinged. Given:

\begin{aligned} \qquad L_{\mathrm{eq}}&=1 \mathrm{m} \\ \text { Slenderness ratio }&=\frac{\mathrm{L}_{\mathrm{eq}}}{r_{\min }} \\ r_{\min }= \sqrt{\frac{I_{\min }}{A}}&=\frac{\sqrt{\frac{1}{12} \times(10)^{3} \times 20 \times 10^{-12}} }{10 \times 20 \times 10^{-6}}\\ &=2.88 \times 10^{-3}\\ \text{Slenderness }&=\frac{1}{2.88 \times 10^{-3}}=347.22 \approx 346 \end{aligned}

\begin{aligned} \qquad L_{\mathrm{eq}}&=1 \mathrm{m} \\ \text { Slenderness ratio }&=\frac{\mathrm{L}_{\mathrm{eq}}}{r_{\min }} \\ r_{\min }= \sqrt{\frac{I_{\min }}{A}}&=\frac{\sqrt{\frac{1}{12} \times(10)^{3} \times 20 \times 10^{-12}} }{10 \times 20 \times 10^{-6}}\\ &=2.88 \times 10^{-3}\\ \text{Slenderness }&=\frac{1}{2.88 \times 10^{-3}}=347.22 \approx 346 \end{aligned}

There are 10 questions to complete.