Answers for Some Tricky Questions
1. What motor is used in railway engines for traction?
a. DC Shunt motor b. DC Series motor
2. Type of magnetic material used for small motors.
a. Diamagnetic b. paramagnetic c. ferromagnetic
3. Which of the following does not form a real image?
a. Concave b. Convex c. telescope d. microscope
Ans: a) Concave (http://en.wikipedia.org/wiki/Optical_lens)
4. Which material has the highest Cp value?
a. air b. water c. copper
Cp for air= 1.005 KJ/Kg K
Cp for water= 4.187 KJ/Kg K
Cp for copper= 0.385 KJ/Kg K
Hence water has the highest value of specific heat capacity under constant pressure. This may be due to the higher degrees of freedom which water possesses.
5. Which of the following has lowest thermal conductivity?
a. steel b. Stainless Steel c. Bronze d. copper
Ans: b) Stainless steel
6. Material is not removed in which process
a. punching b. coining c. tapping d. embossing
All the above are metal forming processes (Not sure)
7. Silencer reduces noise. It also
a. gives balance to engine b. increases fuel consumption c. Decreases fuel consumption d. reduces vibrations
Ans: b) Increases fuel consumption (http://www.natew.com/rcheli/frame_main.cgi/html.Exhaust)
These questions have no option
8. What types motor is used for running lathe spindle?
9. Instrument used for measurement of high temperatures? PYROMETERS
10. Meaning of overdrive
A gear set in which the output shaft turns faster than the input shaft. Overdrive gears are used in most modern transmissions because they reduce engine rpm and improve fuel economy. Occasionally, a separate gearbox with an overdrive gear set is coupled to a conventional transmission. (www.autocenter.com)
11. Wankel engine
The Wankel engine is a type of internal combustion engine, invented by Felix Wankel, which uses a rotor instead of reciprocating pistons. This design promises smooth high-rpm power from a compact, lightweight engine; however Wankel engines are criticized for poor fuel efficiency and exhaust emissions. (en.wikipedia.org/wiki/Wankel_engine)
|