1
GATE PI 1995
MCQ (Single Correct Answer)
+5
-1.5
In an orthogonal machining experiment using a tool having $${6^ \circ }.$$ Rake angle, the following data were collected. Cutting speed $$0.5$$ $$m/sec,$$ width of cut $$3$$ $$mm,$$ depth of cut $$1mn,$$ chip thickness $$1.5mm.$$ Assuming that shearing takes place under minimum energy condition,

Chip velocity is

A
$$10m/min$$
B
$$20m/min$$
C
$$30m/min$$
D
$$40m/min$$
2
GATE PI 1994
Subjective
+5
-0
A part can be machined in $$30$$ minutes on an engine lathe where as it can be machined in $$6$$ minutes on a turret lathe. However, it would cost additionally Rs. $$500$$ to tool up the turret lathe for the operation. If the hourly rate including labour and overhead is Rs. $$80$$ for the engine lathe and Rs. $$160$$ for the turret lathe, The minimum number of parts required to make the turret lathe more economical to use, for the operation
3
GATE PI 1994
MCQ (Single Correct Answer)
+5
-1.5
In an orthogonal cutting operation,
The depth of cut $$=2$$ $$mm,$$
Width of cut $$=15$$ $$mm,$$
Cutting speed $$=0.5$$ $$m/s$$ and
The rake angle $$=0$$ deg.
The cutting force and the thrust force are respectively $$900$$ $$N$$ and $$600$$ $$N$$ and the shear angle $$=30$$ $$deg$$.

The cutting power in watts is

A
$$300$$
B
$$450$$
C
$$600$$
D
$$750$$
4
GATE PI 1994
MCQ (Single Correct Answer)
+5
-1.5
In an orthogonal cutting operation,
The depth of cut $$=2$$ $$mm,$$
Width of cut $$=15$$ $$mm,$$
Cutting speed $$=0.5$$ $$m/s$$ and
The rake angle $$=0$$ deg.
The cutting force and the thrust force are respectively $$900$$ $$N$$ and $$600$$ $$N$$ and the shear angle $$=30$$ $$deg$$.

The average coefficient of friction between the chip and the tool is

A
$$1/3$$
B
$$3/5$$
C
$$2/3$$
D
none