A stone is projected vertically upwards with a velocity of 12ms'. Calculate or find: a) How long it took the stone to reach its maximum height.

b) Maximum height reached by the stone.

To understand the electric potential and electric field of a point charge in three dimensions consider a positive point charge q, located at the origin of three-dimensional space. throughout this problem, use k in place of 14? ? 0. part adue to symmetry, the electric field of a point charge at the origin must point from the origin.answer in one word.part bfind e(r), the magnitude of the electric field at distance r from the point charge q.express your answer in terms of r, k, and q. part cfind v(r), the electric potential at distance rfrom the point charge q.express your answer in terms of r, k, and q part dwhich of the following is the correct relationship between the magnitude of a radial electric field and its associated electric potential ? more than one answer may be correct for the particular case of a point charge at the origin, but you should choose the correct general relationship. a)e(r)=dv(r)drb)e(r)=v(r)rc)e(r)=? dv(r)drd)e(r)=? v(r)r

The smallest particle of an element that retains its identity in a chemical reaction. true or false

Suppose two stars are located in region a of the h-r diagram shown in the figure below. star c appears much dimmer than star y as seen from earth. which star can be inferred to be nearer to earth and how do you know?