Q. A self-aligning ball bearing has a basic dynamic load rating (C10, for 106 revolutions) of 35 kN. If the equivalent radial load on the bearing is 45 kN, the expected life (in 106 revolutions) is (A) below 0.5 (B) 0.5 to 0.8 (C) 0.8 to 1.0 (D) above 1.0 Ans: below 0.5
Q. A carpenter glues a pair of cylindrical wooden logs by bonding their end faces at an angle of q = 30° as shown in the figure. The glue used at the interface fails if Criterion 1: the maximum normal stress exceeds 2.5 MPa. Criterion 2: the maximum shear stress exceeds 1.5 MPa. Assume that the
Q. An epicyclic gear train is shown in the figure below. The number of teeth on the gears A, B and D are 20, 30 and 20, respectively. Gear C has 80 teeth on the inner surface and 100 teeth on the outer surface. If the carrier arm AB is fixed and the sun gear
Q. The state of stress at a point, for a body in plane stress, is shown in the figure below. If the minimum principal stress is 10 kPa, then the normal stress s y(in kPa) is (A) 9.45 (B) 18.88 (C) 37.78 (D) 75.50 Ans: 37.78
The state of stress at a point, for a body in plane stress, is shown in the figure below Read More »
Q. A point mass is shot vertically up from ground level with a velocity of 4 m/s at time, t = 0 . It loses 20% of its impact velocity after each collision with the ground. Assuming that the acceleration due to gravity is 10 m/s2 and that air resistance is negligible, the mass stops
Q. Let X1, X2 be two independent normal random variables with means µ1, µ2 and standard deviations s1, s2, respectively. Consider Y = X1 – X2; µ1 = µ2 =1, s1 = 1, s2 = 2. Then, A. Y is normally distributed with mean 0 and variance 1 B. Y is normally distributed with mean
Q. The height (in mm) for a 125 mm sine bar to measure a taper of 27 ̊ 32¢ on a flat work piece is ____________(correct to three decimal places). Ans: 57.000 – 58.000
Q. For a Pelton wheel with a given water jet velocity, the maximum output power from the Pelton wheel is obtained when the ratio of the bucket speed to the water jet speed is___________(correct to two decimal places). Ans: 0.48 – 0.52 Sol:
Q. A flat plate of width L = 1 m is pushed down with a velocity U = 0.01 m/s towards a wall resulting in the drainage of the fluid between the plate and the wall as shown in the figure. Assume two-dimensional incompressible flow and that the plate remains parallel to the wall. The
Q. If the wire diameter of a compressive helical spring is increased by 2%, the change in spring stiffness (in %) is (correct to two decimal places). Ans: 8.243 Sol: Stiffness of helical spring,
