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1) In case of solid particles present in the liquid and in case of presence of only gas bubbles in liquids, the direction of force is towards a. Areas of maximum stress, areas of minimum stress b. Areas of maximum stress, areas of maximum stress c. Areas of minimum stress, areas of maximum stress d. Areas of minimum stress, areas of minimum stress
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2) According to the Bubble theory, once a bubble is formed, it will elongate in the direction of electric field under the influence of electrostatic forces. During elongation the volume of bubbles a. Increases b. Decreases c. Remains constant d. None of these
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3) According to the Stressed Oil Volume theory, the breakdown strength is a. Directly proportional to the stressed oil volume b. Directly proportional to the square of the stressed oil volume c. Inversely proportional to the stressed oil volume d. None of these
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4) Treeing phenomenon is observed in a. Capacitors b. Cables c. Insulators d. Only (a) and (b)
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5) The liquid dielectrics contain voids or cavities within the medium or at the boundaries between the dielectric and the electrodes. The electric field strength in the voids is a. Lower than that across the dielectric b. Higher than that across the dielectric c. Equal to that across the dielectric d. None of these
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6) For very small cavities, discharge inception voltage a. Decreases as the cavity depth increases b. Increases as the cavity depth increases c. Remains unaffected as the cavity depth increases d. None of these
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7) Which among the following is not an example of impregnants? a. Mineral oil b. Chlorinated diphenyl c. Vegetable oils d. None of these
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8) The example of artificial fibre is a. Rayon b. Cotton c. Flax d. Silk
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9) The most commonly used insulating materials for low and medium voltage cables is a. Polyethylene b. Porcelain c. PVC d. Vulcanized rubber
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10) In paper based laminated construction, the typical value of dielectric constant and dielectric loss factor is a. 3.5, 0.0015 b. 2.5, 0.0020 c. 3.5, 0.0025 d. 2.5, 0.0035
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