You Do Need power plug adapter while traveling from Tanzania to Senegal.

Here is Why You Need An Adapter

The outlet and plug type used in Senegal are C, D, E and K and in Tanzania are D and G. This is how they look like.

Tanzania

In Tanzania, outlets of type D and G are in use.

Type D

Type G

Senegal

In Senegal, outlets of type C, D, E and K are in use.

Type C

Type D

Type E

Type K