Two circular coils P & Q are   fixed coaxially & carry currents${\text{ I}}_{\text{1 }}$ and ${\text{I}}_2$ respectively

 

 

if ${\text{I}}_2$ =0 & P moves towards Q, a current in the same direction as ${\text{I}}_{\text{1}}$ is induced in Q

if ${\text{I}}_1=0 \& Q$  moves  towards P , a current in the opposite direction to  that of ${\text{I}}_2$ is induced in P

when ${\text{I}}_1\ne 0$ and ${\text{I}}_2\ne 0$ are in the same direction then the two coils tends to move apart,

when ${\text{I}}_1\ne 0$ and ${\text{I}}_2\ne 0$  are in opposite direction then the coils tends to move apart