Mafhum-e-Hadith: Sharmgaah chune se wudhu tut jata hai

Bismillahirrahmanirrahim

Mafhum-e-Hadith: Sharmgaah chune se wudhu tut jata hai 

Busrah bint Safwan Radi-Allahu-Anha se rivayat hai ki Rasoollallah Sallallhu-Alaihi-Wasallam ne farmaya jo shaksh apni sharmgaah ko chu le usey chahiye ki wo wudhu karey 
Sunan Nasaii, Vol 1, 447 - Sahih 

Busrah bint Safwan Radi-Allahu-Anha se rivayat hai ki Rasoollallah Sallallhu-Alaihi-Wasallam ne farmaya jo shkash apni sharmgaah ko chu le wo shaksh tab tak namaz na padhe jab tak wudhu na kar le 
Sunan Nasaii, Vol 1, 448 - Sahih 

Aayesha Radi-Allahu-Anha se rivayat hai ki Rasoollallah Sallallhu-Alaihi-Wasallam ghusal karney ke baad wudhu nahi farmatey they (kyunki ghusal karna kafi ho jata hai.) 
Sunan Nasaii, Vol 1, 432 -Hasan 
Note: Ghusal karney ke baad wudhu karna lazim nahi magar badan ko saaf kartey waqt agar haath sharmgaah ko chu jaye to phir usey wudhu karna padhega 

English Translation:
It was narrated from Busrah bint Safwan Radi-Allahu-Anha that the Prophet Peace be upon him said: If any one of you touches his private part with his hand, let him perform Wudu 
Sunan Nasaii, Vol 1, 446 ( Sahih) 

It was narrated from Busrah bint Safwan Radi Allahu Anhu that the Prophet Sallallahu Alaihi Wasallam said: Whoever touches his penis, he should not perform Salah until he performs Wudu 
Sunan Nasaii, Vol. 1, Book 4, 448-Sahih 

It was narrated by Aisha Radi-Allahu-Anha that the Messenger of Allah Peace be upon him would not perform Wudhu (Ablution) after Ghusl (Bath) 
Sunan Nasaii, Vol 1, 430 (Hasan)

Note: After having bath there is no need to perform Wudhu but while somebody is wiping is body after bath and if he touch his private parts then he should perform wudhu.