BHEL Technical Paper
1. What percentage of carbon is preset in pig iron. (4.5 to 6%)
2. Water is available at 10m height. What is the pressure available?
pressure=density*g*height;
p=1000*9.81*10;
p=98100N/m2
3. What will happen if the speed of the centrifugal pump doubles.
4 . The unit eV is widely used in ? (Nuclear and atomic physics)
5. What will happen to the resistance, when the diameter of the conductor is doubled?
6. The power consumed by a electrical device is 1000W at 250V, What is the resistance in thedevice?
Power= Voltage*current;
Current=Power/Voltage,
Current, I=1000/250=4amps.
V=IR,
Therefore R=250/4=62.5 ohms
7. Why DC current is not used in transformer.
8. On what principle the sonar/ radar works?
9. Bending moment diagram for the UDL is in what shape?
10.Function of the distributor in petrol vehicles? (Spark timing)
11.Which is not present in CI engines? (carburetors)
12.What will happen if one cylinder receives more amount of fuel spray from injectors than other injectors?
13.Purpose of draft tube in hydraulic turbines?
The purpose of a draft tube is to convert some of the kinetic energy of the flow from the runner (the rotating part of the turbine) into pressure energyand thereby increase the efficiency ofthe hydro power turbine.
14.What is the effect or reheated in the gas turbine? (The advantage of reheater is significantly increased thrust; the disadvantage is it has very high fuel consumption and inefficiency)
15.Problems involving with frication coefficient.
16.Factor of safety = Yeild stress/Working stress.
17.Which is the example of non parallel power transmission (Universal coupling)
18.For perpendicular shafts ----- is used.
19.A planet gear with 25 teeth is meshed with a sun gear of 100 teeth. Both are connected using aarm. How many rotations are needed for planet gear to complete one rotation around the sun gear?
20.What is equivalent spring constant for spring in parallel?
21.How are tungsten and sintered composite materials are machined? (Electro Discharge Machining, EDM)
22.An elevator weighing 1000kg attains an upward velocity of 4m/sec in two seconds with uniform acceleration. The tension in the supporting cables will be = 1200kg.
23. A 13m ladder is placed against a smooth vertical wall with its lower end 5m from the wall. What should be the co-efficient of friction between ladder and floor so that it remains in equilibrium. =0.21
24. A car is moving with a velocity of 60km/hr and possesses energy of 5Ã105 joules. The mass of the car will be. =3000kg.
25.If l is the span of a light suspension bridge whose each cable carries total weight (w) and the central diop is y, the horizontal pull at each support is:
26. A beam of length l, having uniform load w kg/unit length is supported freely at the ends. The moments at mid span will be: = wl2/8.
27. A boiler shell 200cm dia and plate thickness 1.5cm is subjected to internal pressure of 1.5MN/m2, then the hoop stress will be. = 100N/m2
28.100KW is to be transmitted by each of two separate shafts. A is turning at 250rpm and B at300rpm. Which shaft must have greater diameter.
29.Two identical leaf springs of spring constant k are arranged like cantilevers in parallel and attached at free end by a spring of spring constant k. The equivalent spring constant of combinationis; = 1.5k.
30.Automobile steering gear is an example of: = lower pair.