Two blocks connected by a spring rest on a smooth horizontal plane as shown in fig. A constant force F starts acting on block ${\text{m}}_{\text{2}}$ as shown in the figure. Which of the following statements are not correct

$\therefore \text{a}=\frac{\text{F}}{{\text{m}}_{\text{1}}+{\text{m}}_{\text{2}}}$

$\therefore {\text{a}}_{\text{cm}}=\frac{\text{F}}{{\text{m}}_{\text{1}}+{\text{m}}_{\text{2}}}$

Initially there is no tension in the spring so initial acceleration of ${\text{m}}_{\text{2}}\text{is}\frac{\text{F}}{{\text{m}}_{\text{2}}}$ , due to this tension developed in the spring so that acceleration of ${\text{m}}_{\text{2}}$ decreases and${\text{m}}_{\text{1}}$  increases from zero initial value the blocks starts to perform SHM about their COM