Q. A ball of mass 3 kg moving with a velocity of 4 m/s undergoes a perfectly-elastic direct-central impact with a stationary ball of mass m. After the impact is over, the kinetic energy of the 3 kg ball is 6 J. The possible value(s) of m is/are              (A) 1 kg only         (B) 6 […]

Q. The derivative of f(x) = cos(x) can be estimated using the approximation (A) < 0.1 % (B) > 0.1 % and < 1 % (C) > 1 % and < 5 % (D) > 5 % Ans: > 0.1 % and < 1 % Sol:

Q. In an electrical discharge machining process, the breakdown voltage across inter electrode gap (IEG) is 200 V and the capacitance of the RC circuit is 50 µF. The energy (in J) released per spark across the IEG is Ans: 1 Sol:

Q. A thin vertical flat plate of height L, and infinite width perpendicular to the plane of the figure, is losing heat to the surroundings by natural convection. The temperatures of the plate and the surroundings, and the properties of the surrounding fluid, are constant. The relationship between the average Nusselt and Rayleigh numbers is

Q. Water enters a circular pipe of length L = 5.0 m and diameter D = 0.20 m with Reynolds number ReD = 500. The velocity profile at the inlet of the pipe is uniform while it is parabolic at the exit. The Reynolds number at the exit of the pipe is     . Ans: 500