Class XII

In an atomic nucleus, neutrons and protons are held together by
  1. gravitational forces
  2. exchange forces
  3. coulombic forces
  4. magnetic forces
The age of most ancient geological formations is estimated by
  1. . Ra - Si method
  2. Potassium - argon method
  3. . C14 method
  4. Uranium - lead method
The dark lines in the solar spectrum are due to
  1. . absorption of corresponding wavelengths by the outer layers of the sun
  2. destructive interference between waves of certain definite wavelengths
  3. . absorption of corresponding wavelengths by the prism used in the photograph
  4. absence of corresponding wavelengths from the light emitted by the core of the sun
Which of the following rays are more penetrating?
  1. Beta rays
  2. Alpha rays
  3. Gamma rays
  4. X-rays
Atoms of an element differ from those of all other elements in
  1. atomic number and electronic configuration
  2. number of neutrons and number of valence electrons
  3. atomic number and number of valence electrons
  4. D. number of neutrons and electronic configuration
Time Elapsed

Question Answered
Score out of 100

Get Started!

we provide the best
services to our students Views


LKG - 12th

Rs 1,999  Annual