Here is a simple representation of my problem.

I want to solve 

```
Solve[(w^2*c^2 /. #) - 1 == 0, w]& /@ {{c -> 1}, {c -> 2}}

```

> 
> 
> ```
> {{{w -> -1}, {w -> 1}}, {{w -> -(1/2)}, {w -> 1/2}}}
> 
> ```
> 
> 

The thing is, I want to combine this with value of `c` like this 

> 
> 
> ```
> {{c->1, w->-1}, {c->1,w->1}, {c->2,w->-1/2}, {c->2,w->1/2}}
> 
> ```
> 
> 

I used 

```
Outer[Union, #, Solve[(w^2*c^2 /. #) - 1 == 0, w]] & /@ {{c -> 1}, {c -> 2}}

```

for this but it gives 

> 
> Rule::argrx: Rule called with 4 arguments; 2 arguments are expected. >>. 
> 
> 
> 

What am I doing wrong? Is there a better way to do this ? 

Note:The example which I gave is simple but my problem is generic. So instead of `w^2*c^2 == 0` there can be any equation which can give any number of solutions.