Answer: hello your question lacks the required diagram attached below is the required diagram
answer : Both cars will move backwards and stop due to friction.
Step-by-step explanation:
Given that both cars are negatively charged, When the wedges are removed both cars will move backwards ( repelling each other ) because they are like poles, and Like poles repel each other. while unlike poles attract each other ( forward movement ) .
The cars will later come to a stop due to frictional forces between the cars and the surface.