BME Machine Design 3

Question 1

In journal bearing design, the Sommerfeld number represents:

Accepted Answer

A dimensionless parameter relating speed, viscosity, load, and geometry

Answer

Bearing load capacity

Answer

Friction force

Answer

Oil film temperature

Question 2

Which type of welded joint is most efficient under tensile loading?

Accepted Answer

Butt joint

Answer

Lap joint

Answer

T-joint

Answer

Corner joint

Question 3

What does 'L10 life' represent for a rolling element bearing?

Accepted Answer

Life at which 90% of bearings will survive

Answer

10% of rated speed

Answer

10 million revolutions at zero load

Answer

10% overload rating

Question 4

A power screw is primarily designed to:

Accepted Answer

Convert rotary motion to linear motion and transmit power

Answer

Fasten two members together

Answer

Absorb shock loads

Answer

Guide sliding motion only

Question 5

The interference fit between a shaft and a hub is designed to transmit load by:

Accepted Answer

Friction from radial pressure

Answer

Key shear

Answer

Bolt clamping

Answer

Adhesive bonding

Question 6

Which failure theory is most appropriate for ductile materials under static loading?

Accepted Answer

Maximum shear stress (Tresca) theory

Answer

Maximum normal stress theory

Answer

Coulomb-Mohr theory

Answer

Maximum normal strain theory