1
GATE PI 1991
Subjective
+5
-0
A resistance welder is rated at $$50$$ $$kVA,$$ at $$50\%$$ duty cycle. Secondary voltage is always constant at $$25$$ volts. If a job requires $$1500$$Amps current, determine the maximum welding time in a total cycle time of $$30$$$$secs$$.
2
GATE PI 1991
+5
-1.5
The voltage-arc length characteristic of a $$DC$$ arc is given by $$V=20+40L.$$ where $$L=$$ arc length in $$cm.$$ The power source characteristics can be approximated by a straight line. Open circuit is $$80V$$ and short circuit current $$1000$$Amps. The optimum arc length in $$mm$$
A
$$0.5$$
B
$$1$$
C
$$5$$
D
$$10$$
3
GATE PI 1991
Fill in the Blanks
+1
-0
Thrust force in drilling can be reduced by .................A............... the point angle and by ..........B.......... the helix angle of the drill

(a) increasing / reducing
(b) increasing / reducing

4
GATE PI 1991
Fill in the Blanks
+1
-0
Increase in rake angle causes ..........A................ in chip thickness and .............B......... in shear angle

(a) increase / reduction
(b) increase / decrease

GATE PI Papers
2017
2016
2015
2014
2013
2012
2011
2010
2009
2008
2007
2006
2005
2004
2003
2002
2001
1995
1994
1993
1992
1991
1990
1989
EXAM MAP
Medical
NEET