Q7.The solidification time of a casting is proportional to (V/A)2, where V is the volume of the
casting and A is the total casting surface area losing heat. Two cubes of same material and
size are cast using sand casting process. The top face of one of the cubes is completely
insulated. The ratio of the solidification time for the cube with top face insulated to that of the
other cube is
Q8.In electrodischarge machining (EDM), if the thermal conductivity of tool is high
and the specific heat of work piece is low, then the tool wear rate and material
removal rate are expected to be respectively
Answer : Option AExplaination / Solution: No Explaination.
Q9.In orthogonal turning of medium carbon steel, the specific machining energy
is 2.0 J/mm3. The cutting velocity, feed and depth of cut are 120 m/min,
0.2 mm/rev. and 2 mm respectively. The main cutting force in N is
Answer : Option DExplaination / Solution: No Explaination.
Q10.A direct current welding machine with a linear power source characteristic provides open circuit voltage of 80 V and short circuit current of 800 A. During welding with the machine, the measured arc current is 500 A corresponding to an arc length of 5.0 mm and the measured arc current is 460 A corresponding to an arc length of 7.0 mm. The linear voltage (E) arc length (L) characteristic of the welding arc can be given as (where E is in volt and L in in mm)
Answer : Option AExplaination / Solution: No Explaination.
Total Question/Mark :
Scored Mark :
Mark for Correct Answer : 1
Mark for Wrong Answer : -0.5
Mark for Left Answer : 0