Q. Which one of the following welding methods provides the highest heat flux (W/mm2)? (A) Oxy-acetylene gas welding (B) Tungsten inert gas welding (C) Plasma arc welding (D) Laser beam welding Ans: Laser beam welding
Which one of the following welding methods provides the highest heat flux (W/mm2)? Read More »
Q. In a casting process, a vertical channel through which molten metal flows downward from pouring basin to runner for reaching the mold cavity is called (A) blister (B) sprue (C) riser (D) pin hole Ans: sprue Sol: In a casting process, a vertical channel through which molten metal flows downward, from the pouring
Q. Consider an ideal vapor compression refrigeration cycle. If the throttling process is replaced by an isentropic expansion process, keeping all the other processes unchanged, which one of the following statements is true for the modified cycle? (A) Coefficient of performance is higher than that of the original cycle. (B) Coefficient of performance
Q. A slender rod of length L, diameter d ( L >> d ) and thermal conductivity k1 is joined with another rod of identical dimensions, but of thermal conductivity k2 , to form a composite cylindrical rod of length 2L . The heat transfer in radial direction and contact resistance are negligible. The effective
Q. As per common design practice, the three types of hydraulic turbines, in descending order of flow rate, are (A) Kaplan, Francis, Pelton (B) Pelton, Francis, Kaplan (C) Francis, Kaplan, Pelton (D) Pelton, Kaplan, Francis Ans: Kaplan, Francis, Pelton
Q. For a hydrodynamically and thermally fully developed laminar flow through a circular pipe of constant cross-section, the Nusselt number at constant wall heat flux ( Nuq ) and that at constant wall temperature ( NuT ) are related as (A) Nuq > NuT (B) Nuq < NuT (C) Nuq = NuT (D) Nuq = (NuT
Q. During a non-flow thermodynamic process (1-2) executed by a perfect gas, the heat interaction is equal to the work interaction (Q1-2 = W1-2) when the process is (A) Isentropic (B) Polytropic (C) Isothermal (D) Adiabatic Ans: Isothermal
Q. A spur gear with 20° full depth teeth is transmitting 20 kW at 200 rad/s. The pitch circle diameter of the gear is 100 mm. The magnitude of the force applied on the gear in the radial direction is (A) 0.36 kN (B) 0.73 kN (C) 1.39 kN (D) 2.78 kN Ans: 0.73
Q. The natural frequencies corresponding to the spring-mass systems I and II are 𝜔𝐼 and 𝜔𝐼𝐼, respectively. The ratio 𝜔𝐼/𝜔𝐼I is Ans: 1/2 Sol:
Q. A flat-faced follower is driven using a circular eccentric cam rotating at a constant angular velocity 𝜔. At time 𝑡 = 0, the vertical position of the follower is 𝑦(0) = 0, and the system is in the configuration shown below. The vertical position of the follower face, 𝑦(𝑡) is given by (A) 𝑒
