MCQOPTIONS
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MCQOPTIONS
This section includes 9 Mcqs, each offering curated multiple-choice questions to sharpen your Mechanical Engineering knowledge and support exam preparation. Choose a topic below to get started.
| 1. |
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 |
| Answer» B. 0.5 to 0.8 | |
| 2. |
For anti-friction bearing, relation between basic dynamic capacity, equivalent load and rating life is |
| A. | \(\frac{C}{P} = (\frac{L}{L_{10}})^{\frac{1}{K}}\) |
| B. | \(\frac{P}{C} = (\frac{L}{L_{10}})^{\frac{1}{K}}\) |
| C. | \(\frac{C}{P} = (\frac{L}{L_{10}})^K\) |
| D. | \(\frac{C}{P} = (\frac{L}{L_{10}})^{2K}\) |
| Answer» B. \(\frac{P}{C} = (\frac{L}{L_{10}})^{\frac{1}{K}}\) | |
| 3. |
For a radial bearing the desired rated life is 10000 hours for a speed of 600 rpm and radial load of 4 kN. The basic load rating (in kN) for the bearing will be |
| A. | 28.45 |
| B. | 38.6 |
| C. | 35.6 |
| D. | 38 |
| Answer» B. 38.6 | |
| 4. |
A natural feed journal bearing of diameter 50 mm and length 50 mm operating at 20 revolution/second carries a load of 2.0 kN. The lubricant used has a viscosity of 20 mPa s. The radial clearance is 50 μm. The Sommerfield number for the bearing is |
| A. | 0.062 |
| B. | 0.125 |
| C. | 0.25 |
| D. | 0.785 |
| Answer» C. 0.25 | |
| 5. |
If the load on a ball bearing is reduced to one third, then its life would increase by |
| A. | 3 times |
| B. | 9 times |
| C. | 27 times |
| D. | 36 times |
| E. | 81 times |
| Answer» D. 36 times | |
| 6. |
If the dynamic load capacity of a ball bearing is increased to 1.5 times its earlier value without changing its equivalent load, the life of the bearing increases to |
| A. | 6.4 times its earlier life |
| B. | 5.2 times its earlier life |
| C. | 4.2 times its earlier life |
| D. | 3.4 times its earlier life |
| Answer» E. | |
| 7. |
In a ball bearing, if the number of balls is reduced to half and diameter of the ball is increased to 4 times, then static load capacity of the ball bearing is |
| A. | reduced 4 times |
| B. | reduced 8 times |
| C. | increased 4 times |
| D. | increased 8 times |
| Answer» E. | |
| 8. |
Find the dynamic load-carrying capacity of a roller bearing if the shaft rotates at 1500 rpm, the radial load acting on the bearing is 6 kN and the expected life for 90% life of the bearing is 8100 hours. |
| A. | 6 kN |
| B. | 44 kN |
| C. | 54000 kN |
| D. | 60000 kN |
| Answer» C. 54000 kN | |
| 9. |
A ball bearing operating at a load F has 8000 hours of life. The life of the bearing, in hours, when the load is doubled to 2F is |
| A. | 8000 |
| B. | 6000 |
| C. | 4000 |
| D. | 1000 |
| Answer» E. | |