# 10 A heat reservoir at 900 K is brought into contact with the ambient at 300K for a short time. During this period 9000 kJ of heat is lost by the heat reservoir. The total loss in availability due to this process is

1.  18000 kJ

2.  9000kJ

3.  6000 kJ

4.  None of the above

4

None of the above

Explanation :
No Explanation available for this question

# In order to bum 1 kilogram of CH4 completely, the minimum number of kilograms of oxygen needed is (take atomic weights of H, C and O as 1, 12 and 16 respectively).

1.  3

2.  4

3.  5

4.  6

4

4

Explanation :
No Explanation available for this question

# The rake angle in a drill

1.  Increases from centre to periphery

2.    Decreases from centre to periphery

3.  remains constant

4.  is irrelevant to the drilling operation

4

Increases from centre to periphery

Explanation :
No Explanation available for this question

# A spring scale indicates a tension T in the right hand cable of the pulley system shown in Figure 5.12. Neglecting the mass of the pulleys and ignoring friction between the cable and pulley the mass m is

1.  2T/g

2.  T(1+e4x)

3.  4T/g

4.  none of the above

4

4T/g

Explanation :
No Explanation available for this question

# Light impurities in the molten metal are prevented from reaching the mould cavity by providing a

1.  Strainer

2.  Button well

3.  Skim bob

4.  all of the above

4

all of the above

Explanation :
No Explanation available for this question

# a quick return mechanism. The crank OA rotates clockwise uniformly. OA = 2cm, OO = 4cm. The ratio of time for forward motion to that for return motion is

1.  0.5

2.  2.0

3.  √2

4.   1

4

2.0

Explanation :
No Explanation available for this question

# The deflection of a spring with 20 active turns under a load of 1000 N is 10 mm. The spring is made into two pieces each of 10 active coils and placed in parallel under the same load. The deflection of this system is

1.   20 mm

2.  10 mm

3.  5 mm

4.  2.5 mm

4

2.5 mm

Explanation :
No Explanation available for this question

# For a given heat flow and for the same thickness, the temperature drop across the material will be maximum for

1.  Copper

2.  Steel

3.  glass-wool

4.    Refractory brick

4

glass-wool

Explanation :
No Explanation available for this question

# The arm OA of an epicyclica gear train shown in Fig. revolves counter clockwise about O with an angular velocity of 4 rad/s. Both gears are of same size. The angular velocity of gear C, if the sun gear B is fixed, is

4

Explanation :
No Explanation available for this question

# Preheating before welding is done to

1.  Make the steel softer

2.  Burn away oil, grease, etc, from the plate surface

3.  Prevent cold cracks

4.    Prevent plate distortion

4