Mechanical Engineering - MCQ Practice Questions

A simple epicyclic gear train is used in an automobile differential. What is its primary function?

In a hydrodynamic bearing, which of the following best describes the wedge film condition?

A shaft is designed to transmit 50 kW at 1500 RPM. If the material has a yield strength of 400 MPa and a factor of safety of 2.5, what is the minimum shaft diameter required using the maximum shear stress theory?

A cast iron flywheel has a mean diameter of 800 mm and rotates at 600 RPM. If the allowable tensile stress is 60 MPa, what is the maximum thickness of the rim?

Which type of key is most suitable for transmitting high torque in rotating shafts with frequent load reversals?

A riveted joint connecting two steel plates has 6 rivets arranged in two rows. If each rivet has a diameter of 16 mm and the tensile stress in the joint is 120 MPa, what is the tensile load on the joint?

A rolling contact bearing has an equivalent dynamic load of 8 kN and a rating life of 10,000 hours at 1500 RPM. Which bearing parameter is most affected by speed and load combination?

Which of the following statements is TRUE regarding stress concentration in machine design?

In a multi-plate clutch, if there are 5 pairs of friction surfaces and the coefficient of friction is 0.3, what is the relationship between the torque transmitted and the axial force?

A deep groove ball bearing is subjected to a radial load of 5 kN and an axial load of 2 kN. If the X and Y factors for this bearing are 0.56 and 1.8 respectively, what is the equivalent dynamic load?

In brake design, which factor is MOST critical when designing brakes for automotive applications operating at high temperatures?

A V-belt drive operates with a belt velocity of 20 m/s and transmits 30 kW. If the belt has a mass of 0.5 kg/m, what is the centrifugal tension in the belt?

A clutch is designed to transmit 15 kW at 1500 rpm. If the coefficient of friction is 0.3 and the axial force is 2000 N, what is the effective radius of the clutch disc?

A flat belt connects two pulleys with diameters 300 mm and 600 mm. The center distance is 1200 mm. Calculate the belt length approximately.

In a helical gear pair with 40° helix angle, what is the axial thrust force if the tangential force is 5000 N?

What is the Lewis form factor for a 20° involute spur gear with 25 teeth?

In a screw-jack with pitch 8 mm and mean diameter 40 mm, if the efficiency is 25%, what is the mechanical advantage?

A wire rope with diameter 16 mm has a tensile strength of 1770 MPa. Calculate the breaking load if the rope has 6×19 construction (core factor = 0.55).

In a sliding contact bearing, which parameter represents the bearing characteristic number?

What is the critical design consideration for a keyway in a shaft?