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A three-phase squirrel cage induction motor has a starting torque of 150% and a maximum torque of 300% with respect to rated torque at rated voltage and rated frequency. Neglect the stator resistance and rotational losses. The value of slip for maximum torque is
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- 13.48%
- 16.24%
- 18.92%
- 26.79%
Correct Option: D
| = | |||||
| Tm | + sm | ||||
| sm | |||||
| ⇒ | = | |||
| 3 | 1 - sm2 |
⇒ sm2 – 4 sm + 1 = 0
| ⇒ sm = | = | (4 - 2 √3) | ||
| 3 | 2 |
= 0.268 = 26.8%.