Dear Student,
Answer to your question is given below:
Yes, potential difference becomes weak in series combination. In series combination, same electric current is present in all components of a circuit. The resistance of the circuit is always more than the resistance of individual resistors in a series combination. Hence, combining in series cannot be a good choice because the same current flows through all the components in a series combination. The total resistance increases in a series combination, it will result in the supply of a weaker potential difference through the circuit.
Regards,