Final answer:
The moment due to friction in a plain journal bearing is impacted by load force, shaft speed, shaft diameter, and bearing materials, due to their influence on contact surface, lubrication, and coefficient of friction. Shaft length and the direction of the force are not directly impactful in this context.
Step-by-step explanation:
The factors that will impact the moment due to friction in a plain journal bearing are several, but among the options provided, the following are correct:
- Load force: The force with which the bearing is loaded will affect the frictional force because it influences the normal force between the contacting surfaces.
- Shaft speed: Higher rotational speeds can influence the frictional moment mainly through thermal effects and lubrication dynamics.
- Shaft Diameter: The diameter of the shaft can affect the surface area in contact and thus change the frictional force and resulting moment.
- Bearing materials (and the resulting coefficient of friction): Different material combinations have different coefficients of friction, which directly affect the frictional force and hence the moment.
It is noted that shaft length does not directly impact the moment due to friction in a plain journal bearing and another factor not applicable here is the direction of the force since frictional force in bearings is typically considered in the circumferential direction, which is perpendicular to the direction of the load force.