Critical Disruptive Voltage in Corona - MCQs with Answers

Critical Disruptive Voltage in Corona - MCQs with Answers

Q1. Air density factor which depends on the pressure and temperature is given by which of these formulas?

a. δ = (5.92 * b) / (273 + t)
b. δ = (7.92 * b) / (273 + t)
c. δ = (3.92 * b) / (273 + t)
d. δ = (4.92 * b) / (273 + t)

View Answer / Hide Answer

Q2. When the voltage applied is equal to the critical disruptive voltage what happens?

a. Corona does not start.
b. Corona starts but is not visible.
c. Corona starts and is visible.
d. Only ionization starts.

View Answer / Hide Answer

Q3. What is the value of energy distance in case of two parallel conductors?

a. (r + 0.301 * √ r)
b. (r + 0.308 * √ r)
c. (r + 0.501 * √ r)
d. (r + 0.508 * √ r)

View Answer / Hide Answer

Q4. As the moisture content in the air increases, what is the effect of this on the disruptive critical voltage?

a. Increases.
b. Decreases.
c. Remains constant.
d. May increases or decrease.

View Answer / Hide Answer

Q5. What is the value of energy distance in case of co-axial conductors?

a. (r + 0.301 * √ r)
b. (r + 0.308 * √ r)
c. (r + 0.501 * √ r)
d. (r + 0.508 * √ r)

View Answer / Hide Answer

Q6. What is the critical disruptive voltage of a three phase line which has a conductor of 2 cm in diameter which are spaced equilaterally 1m apart, if the dielectric strength of air is about 30 kV/cm, and air density about 0.952 and irregularity factor 0.9?

a. 152.36 kV
b. 146.235 kV
c. 144.95 kV
d. 111.235 kV

View Answer / Hide Answer

Q7. By what factor does the critical disruptive voltage (V_d) gets reduced?

a. 0.6
b. 0.7
c. 0.8
d. 0.9

View Answer / Hide Answer