A uniform electric field of $$10 NC^{-1}$$ exists in the vertically downward direction. Find the increase in the electric potential as one goes up through a height of $$50$$ cm.
The electric field in the region is $$E=10 N/c$$
The distance covered by the particle is $$ S=50cm=0.5m$$
The relation between the electric potential and the electric field is :
$$E=\dfrac{dV}{dr}$$
or, $$V=E\times r$$
$$=10\times 0.5=5\ V$$.