You Do Need power plug adapter while traveling from South Sudan to Cambodia.

Here is Why You Need An Adapter

The outlet and plug type used in Cambodia are A, C and G and in South Sudan are C and D. This is how they look like.

South Sudan

In South Sudan, outlets of type C and D are in use.

Type C

Type D

Cambodia

In Cambodia, outlets of type A, C and G are in use.

Type A

Type C

Type G