Question

The ionization potential for second He electron is

(a) 13.6 eV

(b) 27.2 eV

(c) 54.4 eV

(d) 100 eV

Answer

(c) 54.4 eV

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Similar questions

Which of the following molecule is not polar?
The thermal conductivity of a rod depends on:
  1. Length.
  2. Mass.
  3. Area of cross section.
  4. Material of the rod.
If a copper rod carries a direct current, the magnetic field associated with the current will be:

Consider an NPN transistor amplifier in common-emitter configuration. The current gain of the transistor is 100. If the collector current changes by 1 mA, what will be the change in emitter current

(a) 1.1 mA

(b) 1.01 mA

(c) 0.01 mA

(d) 10 mA

A string of negligible thickness is wrapped several times around a cylinder kept on a rough horizontal surface. A man standing at a distance 1 from the cylinder holds one end of the string and pulls the cylinder towards him. There is no slipping anywhere. The length of the string passed through the hand of the man while the cylinder reaches his hands is:
  1. l
  2. 2l
  3. 3l
  4. 4l

The value of photoelectric current depends :

Assertion :  No interference pattern is detected when two coherent sources are infinitely close to each other.

Reason     : The fringe width is inversely proportional to the distance between the two slits.

(a) If both assertion and reason are true and the reason is the correct explanation of the assertion.

(b) If both assertion and reason are true but reason is not the correct explanation of the assertion.

(c) If assertion is true but reason is false.

(d) If the assertion and reason both are false.

The SI unit of volume charge density is:

A coil of area 80 square cm and 50 turns is rotating with 2000 revolutions per minute about an axis perpendicular to a magnetic field of 0.05 Tesla. The maximum value of the e.m.f. developed in it is

(a) 200π volt

(b)  

(c)  

(d)  volt

Thermocouple is a device for the measurement of

(a) Absolute temperature of a metal

(b) The temperature difference between two substances

(c) The couple acting on a wire

(d) Thermal conductivity of a substance