"Through what voltage must an α-particle, with its charge of +2e, be accelerated so that it has just enough energy to reach a distance of 1.7×10−14 m from the surface of a gold nucleus? (Assume the gold nucleus remains stationary and can be treated as a point charge.)"

this is an example of "committed" time.

committed time, as contracted time, takes need over essential and available time since it is seen as profitable work. it alludes to the time allotted to keep up a home and family. at the point when a man is commuting using committed time this individual may feel that the drive is an obligation to family, for example, strolling youngsters to class or driving a mate to work. contracted and committed time clients may feel that their commute could really compare to the commute of important or leisure time clients on the grounds that their commute is profitable work. in this manner, they might be more disposed to pick a mechanized method of movement.  

gravitational energy

electrical energy

kinetic energy

ligh energy

you get 2.3=1.21*\frac{a}2 or 4.6=1.21a or a=3.802 (b)

explanation: