Marine engine shafts experience high radial and axial thrust loads, which require bearings that can support both types of loads effectively.
Step 1: Definition of bearing types.
Deep groove ball bearings (Option A) are good for radial loads but are not ideal for handling significant axial thrust.
Sealed ball bearings (Option B) are used to prevent contamination but are not particularly suited for high thrust loads.
Tapered roller bearings (Option C) are designed to handle both radial and axial loads effectively, making them the most suitable choice for marine engine shafts under high radial and axial thrust.
Needle bearings (Option D) are compact and suitable for smaller spaces but are generally not ideal for high thrust loads.
Step 2: Analyze each option.
(A) Incorrect. Deep groove ball bearings are not designed to handle significant axial thrust.
(B) Incorrect. Sealed ball bearings are not ideal for high radial and axial thrust loads.
(C) Correct. Tapered roller bearings are designed specifically for both radial and axial loads, making them the most suitable option.
(D) Incorrect. Needle bearings are used for lighter loads and are not ideal for high axial thrust.
A closed system is undergoing a reversible process 1–P–2 from state 1 to 2, as shown in the figure, where X and Y are thermodynamic properties. An irreversible process 2–Q–1 brings the system back from 2 to 1. The net change in entropy of the system and surroundings during the above-mentioned cycle are _______ respectively.
