Ruku'

Rukūʿ (Arabic: رُكوع‎) refers to two things in Islam.
1. RUKU is a step of prayer in Islam where someone bows down (places hands on knees) and then goes to Sajdah (placing forehead on the ground).

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Sayyed Mohammad Al-Musawi, Sayyed Mohammad al-Musawi is originally from Iraq and heads up the World Ahlul Bayt Islamic League in London. Other than being involved in various humanitarian projects, he frequently responds to... Answered 1 year ago

Takbeer is recommended before and after actions of Salah, like Rukuu', Sojood. Takbeer should be said when you are steady not moving.

Wassalam.

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Sayyed Mohammad Al-Musawi, Sayyed Mohammad al-Musawi is originally from Iraq and heads up the World Ahlul Bayt Islamic League in London. Other than being involved in various humanitarian projects, he frequently responds to... Answered 1 year ago

Missing Ruku' invalidate Salah because Ruku' is one of the basic five obligatory acts of Salah. If you remembered and performed Ruku; before going for next step, then your Salah will be valid. If you go ahead to next Rak'at, before performing Ruku', then Salah is invalid because of missing one basic obligatory act.

'Wassalam.

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Zaid Alsalami, Shaykh Dr Zaid Alsalami is an Iraqi born scholar, raised in Australia. He obtained a BA from Al-Mustafa University, Qom, and an MA from the Islamic College in London. He also obtained a PhD from... Answered 1 year ago

Bismihi ta'ala

Yes, it would be valid, and there would be no issue with your prayer. 

And Allah knows best

87714

Sayyed Mohammad Al-Musawi, Sayyed Mohammad al-Musawi is originally from Iraq and heads up the World Ahlul Bayt Islamic League in London. Other than being involved in various humanitarian projects, he frequently responds to... Answered 1 year ago

It is recommended and not obligatory to say it. No doubt saying it will bring reward which you will not get if you don’t say it.

Wassalam.

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Sayyed Mohammad Al-Musawi, Sayyed Mohammad al-Musawi is originally from Iraq and heads up the World Ahlul Bayt Islamic League in London. Other than being involved in various humanitarian projects, he frequently responds to... Answered 1 year ago

It is compulsory during Rokoo' ركوع to make your hand touch your knee even if your figure touch your knee. If your hand did not touch your knee during Rokoo', your Rokoo' will be invalid.

Wassalam.

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Sayyed Muhammad Husaini Ragheb, Sayyed Muhammad Husaini Ragheb has a BA in Law from Guilan University, Iran and has also undertaken Hawzah studies in Qom. He used to be a Cultural Affairs director of Ethics Group of Al-Mustafa... Answer updated 2 years ago

Salaam
In Rokou' when you bend down it is enough to repeat سُبْحانَ اللّهِ  (i.e. subḥānal lāh ) three times or say سُبْحانَ رَبِّیَ الْعَظیمِ وَبِحَمْدِهِ (i.e. subḥāna rabbiyal ʿaẓīmi wa biḥamdih ) only once.

If you didn't know the ruling and just bowed down you don't need to repeat those prayers.

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Sayyed Mohammad Al-Musawi, Sayyed Mohammad al-Musawi is originally from Iraq and heads up the World Ahlul Bayt Islamic League in London. Other than being involved in various humanitarian projects, he frequently responds to... Answer updated 4 years ago

If you proceed to Rukoo' before the Imam of Jama'ah or Jum'ah thinking that he is in Rukoo', you need to stand back and return to Rukoo' then follow the Imam. Your Salaah will be valid.

Wassalam.

Abbas Di Palma, Shaykh Abbas Di Palma holds a BA and an MA degree in Islamic Studies, and certifications from the Language Institute of Damascus University. He has also studied traditional Islamic sciences in... Answered 4 years ago

as salam alaikum

in the mentioned case, you should go back in the standing position (qiyam) and continue to follow the Imam. 

With prayers for your success.

63847

Sayyed Mohammad Al-Musawi, Sayyed Mohammad al-Musawi is originally from Iraq and heads up the World Ahlul Bayt Islamic League in London. Other than being involved in various humanitarian projects, he frequently responds to... Answered 4 years ago

It is recommended to say Subhanallah one time or more before Dhikr of Rokoo' and Dhikr of Sojood. If you say Subhanallah three times, it will be like saying Dhikr of Rokoo' or Sojood one time. Repeating Dhikr is recommended either three times or five or seven or nine or more odds.

Wassalam.

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Sayyed Mohammad Al-Musawi, Sayyed Mohammad al-Musawi is originally from Iraq and heads up the World Ahlul Bayt Islamic League in London. Other than being involved in various humanitarian projects, he frequently responds to... Answered 4 years ago

There is no limit of number of times we can repeat he Thikr or Rokoo' or Sojood. It is recommended to repeat it 3 or 5 or 7 or more in odd times.

Wassalam.

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Shahid Pradhan, Shahid Pradhan is a graduate of Al-Mustafa International University, Qum. He is an activist and interested in Indian and international political and social issues. Answer updated 5 years ago

The term قیام متصل برکوع means pausing for a moment after recitation before going to the ruku.

According to the office Ayatullah Sistani (may Allah prolong his life)

1) It's wajib

2) if one goes to the ruku without the mentioned pause, they have to return back to standing position (qiyam) pause for moment then perform the ruku.

Also refer to the following issue will be helpful to you 

969. If a person forgets to perform Ruku, and sits down after reciting Hamd and Surah, and then remembers that he has not performed Ruku, he should first stand up and then go into Ruku. If he does not stand up first, and performs Ruku while he is bowing, his prayers will be void because of not having performed qiyam (standing) before Ruku (Qiyam muttasi'l ba Ruku').

https://www.sistani.org/english/book/48/2220/