MCQOPTIONS
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MCQOPTIONS
This section includes 14 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 solid steel shaft of 100 mm diameter and 1.0 m long is subjected to a twisting moment T. This shaft is to be replaced by a hollow shaft having outer and inner diameters as 100 mm and 50 mm respectively. If the maximum shear stress induced in both the shafts is same, the twisting moment T transmitted by hollow shaft must be reduced by |
| A. | T/4 |
| B. | T/8 |
| C. | T/16 |
| D. | T/12 |
| Answer» D. T/12 | |
| 2. |
In a flange coupling, the flange bolts are designed for |
| A. | Fatigue |
| B. | Shear force |
| C. | Compression |
| D. | Tensile force |
| Answer» C. Compression | |
| 3. |
If a rectangular key of 8 mm width and 6 mm height and a shaft of diameter 32 mm are made of same material, then the necessary length of the key for equal shear strength of shaft and key will be (neglecting stress concentration on the shaft) |
| A. | 50.24 mm |
| B. | 55 mm |
| C. | 45 mm |
| D. | 60.24 mm |
| Answer» B. 55 mm | |
| 4. |
__________ can be used to transmit power between two non-parallel and intersecting shafts |
| A. | Universal Joint |
| B. | Oldham's coupling |
| C. | Revolute joint |
| D. | None of the above |
| Answer» B. Oldham's coupling | |
| 5. |
A shaft of 50 mm diameter transmits a torque of 800 N-m. The width of the rectangular key used is 10 mm. The allowable shear stress of the material of the key being 40 MPa, the required length of the key would be |
| A. | 60 mm |
| B. | 70 mm |
| C. | 80 mm |
| D. | 90 mm |
| Answer» D. 90 mm | |
| 6. |
A key connecting a flange coupling to the shaft is likely to fail in |
| A. | Torsion |
| B. | Tension |
| C. | Shear |
| D. | Bending |
| Answer» D. Bending | |
| 7. |
In a fully automatic transmission the |
| A. | torque is continuously transmitted to the driving wheels |
| B. | power is continuously transmitted to the driving wheels |
| C. | tractive effect is continuously transmitted to the driving wheels |
| D. | driving force is continuously transmitted to the driving wheels |
| Answer» C. tractive effect is continuously transmitted to the driving wheels | |
| 8. |
A key of 14 mm width, 9 mm height and 100 mm length is mounted on a shaft of 50 mm diameter. If allowable shear stress for the key material is 50 MPa, what is the maximum torque that can be transmitted? |
| A. | 3500 Nm |
| B. | 4500 Nm |
| C. | 2250 Nm |
| D. | 1750 Nm |
| Answer» E. | |
| 9. |
If a solid circular shaft of steel 2 cm in diameter is subjected to a permissible shear stress of 10 kN/cm2, then the value of the twisting moment (Tr) will be) |
| A. | 10π kN-cm |
| B. | 20π kN-cm |
| C. | 15π kN-cm |
| D. | 5π kN-cm |
| Answer» E. | |
| 10. |
If the permissible crushing stress for the material of a key is double the permissible shear stress, then the sunk key will be equally strong in shearing and crushing if the key is a |
| A. | Rectangular key with width equal to half the thickness |
| B. | Rectangular key with width equal to twice the thickness |
| C. | Square key |
| D. | Rectangular key with width equal to one-fourth the thickness |
| Answer» D. Rectangular key with width equal to one-fourth the thickness | |
| 11. |
Oldham’s coupling contains: |
| A. | 2 turning pairs and 2 sliding pairs |
| B. | 1 turning pairs and 3 sliding pairs |
| C. | 2 turning pairs and 1 sliding pairs |
| D. | 3 turning pairs and 1 sliding pairs |
| Answer» B. 1 turning pairs and 3 sliding pairs | |
| 12. |
A shaft has two heavy rotors mounted on it. The transverse natural frequencies, considering each of the rotor separately are 100 cycles/sec and 200 cycles/sec respectively. The lowest critical speed is |
| A. | 6000 rpm |
| B. | 9360 rpm |
| C. | 5367 rpm |
| D. | 1259 rpm |
| Answer» D. 1259 rpm | |
| 13. |
A shaft revolving at ω rad/s transmits torque (T) in N-m. The power developed is |
| A. | T × ω Watts |
| B. | 2πTω Watts |
| C. | \( \frac{{2\pi T\omega}}{{75}}\) Watts |
| D. | \( \frac{{2\pi T\omega}}{{4500}}\) Watts |
| Answer» B. 2πTω Watts | |
| 14. |
In hydraulic coupling |
| A. | The magnitudes of input and output torques are equal |
| B. | The magnitude of input torque is greater than output torque |
| C. | The magnitude of input torque is less than output torque |
| D. | The magnitude of input torque is negligible as compared to output torque |
| Answer» B. The magnitude of input torque is greater than output torque | |