Ionization of Air

Q. An electric field of $5,000,000\frac{V}{m}$ is applied across a region filled with air at atmospheric pressure. What will happen? (Dielectric strength of air is $3,000,000\frac{V}{m}$

1. Nothing happens
2. Air begins to conduct and we get sparks
3. Fusion reaction takes place between air molecules
4. The zombie apocalypse starts

Q. What happens to the deflection of the compass needle placed at a point near current-carrying straight conductor, if :
(a) If the current is increased?
(b) If the direction of current in the conductor is reversed?
(c) If the compass is moved away from the conductor?

Q. Charge is continuously fed to a conductor. What should the minimum charge density at any point be to give corona discharge when the conductor is kept in air?
(Dielectric strength of air is $3,000,000\frac{V}{m}$

1. $4,000,000{\epsilon }_0$
2. $3,000,000{\epsilon }_0$
3. $2,000,000{\epsilon }_0$
4. $1,000,000{\epsilon }_0$

Q. Which thermogalvanic effect takes place in a single conductor?

1. Seebeck effect
2. Petlier effect
3. Joule effect
4. Thomson effect

Q. Charge is continuously fed to a conductor. What should the minimum charge density at any point be to give corona discharge when the conductor is kept in air?
(Dielectric strength of air is $3,000,000\frac{V}{m}$

1. $4,000,000{\epsilon }_0$
2. $3,000,000{\epsilon }_0$
3. $2,000,000{\epsilon }_0$
4. $1,000,000{\epsilon }_0$

Q. An electric field of $5,000,000\frac{V}{m}$ is applied across a region filled with air at atmospheric pressure. What will happen? (Dielectric strength of air is $3,000,000\frac{V}{m}$

1. Nothing happens
2. Fusion reaction takes place between air molecules
3. Air begins to conduct and we get sparks
4. The zombie apocalypse starts

Q. Assertion :The current density $\overrightarrow{J}$ at any point in ohmic resistor is in the direction of electric field $\overrightarrow{E}$ at that point. Reason: A point charge when released from rest in a region having only electrostatic field always moves along electric lines of force.

1. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
2. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
3. Assertion is correct but Reason is incorrect
4. Both Assertion and Reason are incorrect

Q. Charge is continuously fed to a conductor. What should the minimum charge density at any point be to give corona discharge when the conductor is kept in air?
(Dielectric strength of air is $3,000,000\frac{V}{m}$

1. $4,000,000{\epsilon }_0$
2. $3,000,000{\epsilon }_0$
3. $2,000,000{\epsilon }_0$
4. $1,000,000{\epsilon }_0$