An electron falls through a distance of \(1.5~\text{cm}\) in a uniform electric field of magnitude \(2\times10^4~\text{N/C}\) [figure (a)]. The direction of the field is reversed keeping its magnitude unchanged and a proton falls through the same distance [figure (b)]. If \(t_e\) and \(t_p\) are the time of fall for electron and proton respectively, then:
1. \(t_e=t_p\)
2. \(t_e>t_p\)
3. \(t_e<t_p\)
4. none of these
Two-point charges and , of magnitude and , respectively, are placed 0.1 m apart. The electric field at point A (as shown in the figure) is: