A ball, of mass 100. g, is dropped from a height of 12. m. Its momentum when it strikes the ground ...

A ball, of mass 100. g, is dropped from a height of 12. m. Its momentum when it strikes the ground is
 
  A) 1.5 kgm/s.
  B) 4.8 kgm/s.
  C) 3.3 kgm/s.
  D) 2.4 kgm/s.
  E) 1.8 kgm/s.

Question 2

Charge +2q is placed at the origin and charge -q is placed at x = 2a. Where can a third positive charge +q be placed so that the force on it is zero?
 
  What will be an ideal response?

Question 3

All of the most likely alternatives to water as a biological solvent are liquids at
 
  A) higher temperatures
  B) lower temperatures
  C) lower pressures
  D) similar temperatures